Journal articles: 'Genetic analysis; Flies; Traits'

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Cowley, D. E., and W. R. Atchley. "Quantitative Genetics of Drosophila Melanogaster. II. Heritabilities and Genetic Correlations between Sexes for Head and Thorax Traits." Genetics 119, no. 2 (June 1, 1988): 421–33. http://dx.doi.org/10.1093/genetics/119.2.421.

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Abstract A quantitative genetic analysis is reported for traits on the head and thorax of adult fruit flies, Drosophila melanogaster. Females are larger than males, and the magnitude of sexual dimorphism is similar for traits derived from the same imaginal disc, but the level of sexual dimorphism varies widely across discs. The greatest difference between males and females occurs for the dimensions of the sclerotized mouthparts of the proboscis. Most of the traits studied are highly heritable with heritabilities ranging from 0.26 to 0.84 for males and 0.27 to 0.81 for females. In general, heritabilities are slightly higher for males, possibly reflecting the effect of dosage compensation on X-linked variance. The X chromosome contributes substantially to variance for many of these traits, and including results reported elsewhere, the variance for over two-thirds of the traits studied includes X-linked variance. The genetic correlations between sexes for the same trait are generally high and close to unity. Coupled with the small differences in the traits between sexes for heritabilities and phenotypic variances, these results suggest that selection would be very slow to change the level of sexual dimorphism in size of various body parts.

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Ling, Ashley, Taylor Krause, Bradley Heins, Nancy Hinkle, Dean Pringle, Samuel E. Aggrey, and Romdhane Rekaya. "48 Genetic study of horn fly abundance in beef cattle." Journal of Animal Science 98, Supplement_4 (November 3, 2020): 16–17. http://dx.doi.org/10.1093/jas/skaa278.031.

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Abstract Disturbing the non-symbiotic relationship between horn flies and cattle is of economic, health, and animal welfare importance. Reliance on management and insecticides has proven inadequate. In the United States, horn flies are estimated to cause more than $1 billion in economic losses on pastured cattle annually. Although insecticides provide temporary control, their efficacy is hampered by several factors. Intensive insecticide use has led to horn fly resistance and decreased predation on horn flies by other insects. Due to the cost and logistic complexity of measuring fly resistance traits under commercial conditions, the genetic basis of these traits remains largely unknown. Only a few heritability estimates are available based on small-scale studies. Currently, the economic injury threshold (EIT) due to horn fly abundance (onset of production decay) is set at around 200 flies for beef cattle. This threshold is largely heuristically set. Additionally, the rate of decay in performance as a function of fly abundance after injury onset is unknown. It is also likely that EIT is breed and animal specific. Data used in this study was collected during the summer of 2019. Animals were not treated or managed in any way to control horn flies prior to data collection. Animals were assessed subjectively and based on image counts for horn fly abundance. Estimates of heritability of horn fly abundance ranged between 0.14 and 0.22 for subjective and image-based phenotypes. The lowest heritability was for the subjective assessment, likely due to the excessive variation between evaluators. Changepoint model-based analysis showed that EIT is variable between sire families, ranging from 265 to 413 flies. Furthermore, there was significant difference in the decay of performance after the onset of injury. The rate of decay ranged between -0.0003 and -0.00018. Collectively, these results indicate the potential to improve horn fly resistance/tolerance using genetic tools.

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Pegueroles, Glòria, Francesc Mestres, Mercè Argemí, and Lluís Serra. "Phenotypic plasticity in colonizing populations of Drosophila subobscura." Genetics and Molecular Biology 22, no. 4 (December 1999): 511–16. http://dx.doi.org/10.1590/s1415-47571999000400008.

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The phenotypic plasticity of some quantitative traits of two colonizing populations of Drosophila subobscura (Davis and Eureka, California) was studied. Temperature effects and the effect of rearing in the laboratory were studied. Laboratory rearing during four generations at 18ºC significantly increased the wing and tibial length. This increase was similar to that obtained when the flies were reared at 13ºC during two generations.The low temperature environment can be considered more stressful for females than for males, as shown by the increase of phenotypic variance. The two populations analyzed had great phenotypic plasticity in spite of the genetic bottleneck during the colonization event. Our study shows that keeping flies for a relatively short time in the laboratory significantly changes some quantitative traits, emphasizing the need to analyze flies immediately after collecting them in order to obtain reliable estimates for the analysis of these traits in natural populations.

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Kopp, Artyom, Rita M. Graze, Shizhong Xu, Sean B. Carroll, and Sergey V. Nuzhdin. "Quantitative Trait Loci Responsible for Variation in Sexually Dimorphic Traits in Drosophila melanogaster." Genetics 163, no. 2 (February 1, 2003): 771–87. http://dx.doi.org/10.1093/genetics/163.2.771.

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Abstract To understand the mechanisms of morphological evolution and species divergence, it is essential to elucidate the genetic basis of variation in natural populations. Sexually dimorphic characters, which evolve rapidly both within and among species, present attractive models for addressing these questions. In this report, we map quantitative trait loci (QTL) responsible for variation in sexually dimorphic traits (abdominal pigmentation and the number of ventral abdominal bristles and sex comb teeth) in a natural population of Drosophila melanogaster. To capture the pattern of genetic variation present in the wild, a panel of recombinant inbred lines was created from two heterozygous flies taken directly from nature. High-resolution mapping was made possible by cytological markers at the average density of one per 2 cM. We have used a new Bayesian algorithm that allows QTL mapping based on all markers simultaneously. With this approach, we were able to detect small-effect QTL that were not evident in single-marker analyses. Our results show that at least for some sexually dimorphic traits, a small number of QTL account for the majority of genetic variation. The three strongest QTL account for >60% of variation in the number of ventral abdominal bristles. Strikingly, a single QTL accounts for almost 60% of variation in female abdominal pigmentation. This QTL maps to the chromosomal region that Robertson et al. have found to affect female abdominal pigmentation in other populations of D. melanogaster. Using quantitative complementation tests, we demonstrate that this QTL is allelic to the bric a brac gene, whose expression has previously been shown to correlate with interspecific differences in pigmentation. Multiple bab alleles that confer distinct phenotypes appear to segregate in natural populations at appreciable frequencies, suggesting that intraspecific and interspecific variation in abdominal pigmentation may share a similar genetic basis.

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Nagle, Keith J., and William J. Bell. "Genetic control of the search tactic ofDrosophila melanogaster: An ethometric analysis ofrover/sitter traits in adult flies." Behavior Genetics 17, no. 4 (July 1987): 385–408. http://dx.doi.org/10.1007/bf01068138.

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Laursen, Stine Frey, Laura Skrubbeltrang Hansen, Simon Bahrndorff, Hanne Marie Nielsen, Natasja Krog Noer, David Renault, Goutam Sahana, Jesper Givskov Sørensen, and Torsten Nygaard Kristensen. "Contrasting Manual and Automated Assessment of Thermal Stress Responses and Larval Body Size in Black Soldier Flies and Houseflies." Insects 12, no. 5 (April 22, 2021): 380. http://dx.doi.org/10.3390/insects12050380.

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Within ecophysiological and genetic studies on insects, morphological and physiological traits are commonly assessed and phenotypes are typically obtained from manual measurements on numerous individuals. Manual observations are, however, time consuming, can introduce observer bias and are prone to human error. Here, we contrast results obtained from manual assessment of larval size and thermal tolerance traits in black soldier flies (Hermetia illucens) and houseflies (Musca domestica) that have been acclimated under three different temperature regimes with those obtained automatically using an image analysis software (Noldus EthoVision XT). We found that (i) larval size estimates of both species, obtained by manual weighing or by using the software, were highly correlated, (ii) measures of heat and cold tolerance using manual and automated approaches provided qualitatively similar results, and (iii) by using the software we obtained quantifiable information on stress responses and acclimation effects of potentially higher ecological relevance than the endpoint traits that are typically assessed when manual assessments are used. Based on these findings, we argue that automated assessment of insect stress responses and largescale phenotyping of morphological traits such as size will provide new opportunities within many disciplines where accurate and largescale phenotyping of insects is required.

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Johns, Philip M., L. LaReesa Wolfenbarger, and Gerald S. Wilkinson. "Genetic linkage between a sexually selected trait and X chromosome meiotic drive." Proceedings of the Royal Society B: Biological Sciences 272, no. 1576 (August 23, 2005): 2097–103. http://dx.doi.org/10.1098/rspb.2005.3183.

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Previous studies on the stalk-eyed fly, Cyrtodiopsis dalmanni , have shown that males with long eye-stalks win contests and are preferred by females, and artificial selection on male relative eye span alters brood sex-ratios. Subsequent theory proposes that X-linked meiotic drive can catalyse the evolution of mate preferences when drive is linked to ornament genes. Here we test this prediction by mapping meiotic drive and quantitative trait loci (QTL) for eye span. To map QTL we genotyped 24 microsatellite loci using 1228 F2 flies from two crosses between lines selected for long or short eye span. The crosses differed by presence or absence of a drive X chromosome, X D , in the parental male. Linkage analysis reveals that X D dramatically reduces recombination between X and X D chromosomes. In the X D cross, half of the F2 males carried the drive haplotype, produced partially elongated spermatids and female-biased broods, and had shorter eye span. The largest QTL mapped 1.3 cM from drive on the X chromosome and explained 36% of the variation in male eye span while another QTL mapped to an autosomal region that suppresses drive. These results indicate that selfish genetic elements that distort the sex-ratio can influence the evolution of exaggerated traits.

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Pletcher, Scott D., David Houle, and James W. Curtsinger. "The Evolution of Age-Specific Mortality Rates in Drosophila melanogaster: Genetic Divergence Among Unselected Lines." Genetics 153, no. 2 (October 1, 1999): 813–23. http://dx.doi.org/10.1093/genetics/153.2.813.

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Abstract Age-specific effects of spontaneous mutations on mortality rates in Drosophila are inferred from three large demographic experiments. Data were collected from inbred lines that were allowed to accumulate spontaneous mutations for 10, 19, and 47 generations. Estimates of age-specific mutational variance for mortality were based on data from all three experiments, totalling ∼225,000 flies, using a model developed for genetic analysis of age-dependent traits (the character process model). Both within- and among-generation analyses suggest that the input of genetic variance is greater for early life mortality rates than for mortality at older ages. In females, age-specific mutational variances ranged over an order of magnitude from 5.96 × 10-3 at 2 wk posteclosion to 0.02 × 10-3 at 7 wk. The male data show a similar pattern. Age-specific genetic variances were substantially less at generation 47 than at generation 19—an unexplained observation that is likely due to block effects. Mutational correlations among mortality rates at different ages tend to increase with the accumulation of new mutations. Comparison of the mutation-accumulation lines at generations 19 and 47 with their respective control lines suggests little age-specific mutational bias.

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Gibert, Patricia, Brigitte Moreteau, Jean-Claude Moreteau, and Jean R. David. "Genetic variability of quantitative traits in Drosophila melanogaster (fruit fly) natural populations: analysis of wild-living flies and of several laboratory generations." Heredity 80, no. 3 (March 1998): 326–35. http://dx.doi.org/10.1046/j.1365-2540.1998.00301.x.

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Hosokawa, Takahiro, Yoshitomo Kikuchi, Naruo Nikoh, Xian-Ying Meng, Mantaro Hironaka, and Takema Fukatsu. "Phylogenetic Position and Peculiar Genetic Traits of a Midgut Bacterial Symbiont of the Stinkbug Parastrachia japonensis." Applied and Environmental Microbiology 76, no. 13 (May 7, 2010): 4130–35. http://dx.doi.org/10.1128/aem.00616-10.

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ABSTRACT The stinkbug Parastrachia japonensis (Hemiptera: Parastrachiidae) is known for its prolonged prereproductive nonfeeding period, maternal care of eggs in an underground nest, and maternal collection and provisioning of food (fruits) for nymphs. A previous study suggested that a bacterial symbiont is involved in uric acid recycling in this insect during the nonfeeding period, but the identity of this symbiont has not been determined. Here we characterized a novel bacterial symbiont obtained from P. japonensis. Molecular phylogenetic analyses based on 16S rRNA, gyrB, and groEL gene sequences consistently indicated that this symbiont constituted a distinct lineage in the Gammaproteobacteria that has no close relatives but is allied with gut symbionts of acanthosomatid and plataspid stinkbugs, as well as with endocellular symbionts of sharpshooters, tsetse flies, and aphids. The symbiont genes had a remarkably AT-biased nucleotide composition and exhibited significantly accelerated molecular evolution. The symbiont genome was extremely reduced; its size was estimated to be 0.85 Mb. These results suggest that there has been an intimate host-symbiont association over evolutionary time. The symbiont was localized in swollen crypts in a posterior part of the midgut, which was a specialized symbiotic organ. The possibility that the symbiont is involved in uric acid recycling is discussed. The designation “Candidatus Benitsuchiphilus tojoi” is proposed for the symbiont.

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Campbell, Nicholas G., Aparna Shekar, Jenny I. Aguilar, Dungeng Peng, Vikas Navratna, Dongxue Yang, Alexander N. Morley, et al. "Structural, functional, and behavioral insights of dopamine dysfunction revealed by a deletion inSLC6A3." Proceedings of the National Academy of Sciences 116, no. 9 (February 12, 2019): 3853–62. http://dx.doi.org/10.1073/pnas.1816247116.

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The human dopamine (DA) transporter (hDAT) mediates clearance of DA. Genetic variants in hDAT have been associated with DA dysfunction, a complication associated with several brain disorders, including autism spectrum disorder (ASD). Here, we investigated the structural and behavioral bases of an ASD-associated in-frame deletion in hDAT at N336 (∆N336). We uncovered that the deletion promoted a previously unobserved conformation of the intracellular gate of the transporter, likely representing the rate-limiting step of the transport process. It is defined by a “half-open and inward-facing” state (HOIF) of the intracellular gate that is stabilized by a network of interactions conserved phylogenetically, as we demonstrated in hDAT by Rosetta molecular modeling and fine-grained simulations, as well as in its bacterial homolog leucine transporter by electron paramagnetic resonance analysis and X-ray crystallography. The stabilization of the HOIF state is associated both with DA dysfunctions demonstrated in isolated brains ofDrosophila melanogasterexpressing hDAT ∆N336 and with abnormal behaviors observed at high-time resolution. These flies display increased fear, impaired social interactions, and locomotion traits we associate with DA dysfunction and the HOIF state. Together, our results describe how a genetic variation causes DA dysfunction and abnormal behaviors by stabilizing a HOIF state of the transporter.

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Krebs, Robert A., and Volker Loeschcke. "Acclimation and Selection for Increased Resistance to Thermal Stress in Drosophila buzzatii." Genetics 142, no. 2 (February 1, 1996): 471–79. http://dx.doi.org/10.1093/genetics/142.2.471.

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Abstract Direct selection for increased resistance to a heat shock (41.9° for 90 min) was carried out using two replicate lines of Drosophila buzzatii that were derived from a large base population. Selected individuals were first acclimated to high temperature before selection, while control individuals were acclimated but not selected, and selection was performed every second generation. Resistance to heat shock with acclimation increased in selected lines. Without acclimation, a correlated smaller increase in heat-shock resistance was suggested. Survival of males was higher than that of females in all lines when tested with acclimation, but with direct exposure to high temperatures, survival of females was greater than that of males both in selection and control lines but not in the base population. From analysis of reciprocal cross progeny between lines, one selection line was found to possess a dominant autosomal factor that significantly increased resistance of males much more than resistance of females. Also suggestive was recessive traits on the X chromosome in both selection lines that increased thermotolerance. No cytoplasmic effects were found. After accounting for other effects, survival of F1 flies was intermediate, suggesting that additive variation is present for one or more of the autosomes.

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Chaston, John M., Adam J. Dobson, Peter D. Newell, and Angela E. Douglas. "Host Genetic Control of the Microbiota Mediates the Drosophila Nutritional Phenotype." Applied and Environmental Microbiology 82, no. 2 (November 13, 2015): 671–79. http://dx.doi.org/10.1128/aem.03301-15.

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ABSTRACTA wealth of studies has demonstrated that resident microorganisms (microbiota) influence the pattern of nutrient allocation to animal protein and energy stores, but it is unclear how the effects of the microbiota interact with other determinants of animal nutrition, including animal genetic factors and diet. Here, we demonstrate that members of the gut microbiota inDrosophila melanogastermediate the effect of certain animal genetic determinants on an important nutritional trait, triglyceride (lipid) content. Parallel analysis of the taxonomic composition of the associated bacterial community and host nutritional indices (glucose, glycogen, triglyceride, and protein contents) in multipleDrosophilagenotypes revealed significant associations between the abundance of certain microbial taxa, especiallyAcetobacteraceaeandXanthamonadaceae, and host nutritional phenotype. By a genome-wide association study ofDrosophilalines colonized with a defined microbiota, multiple host genes were statistically associated with the abundance of one bacterium,Acetobacter tropicalis. Experiments using mutantDrosophilavalidated the genetic association evidence and reveal that host genetic control of microbiota abundance affects the nutritional status of the flies. These data indicate that the abundance of the resident microbiota is influenced by host genotype, with consequent effects on nutrient allocation patterns, demonstrating that host genetic control of the microbiome contributes to the genotype-phenotype relationship of the animal host.

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KARAN, DEV, ASHOK K. MUNJAL, PATRICIA GIBERT, BRIGITTE MORETEAU, RAVI PARKASH, and JEAN R. DAVID. "Latitudinal clines for morphometrical traits in Drosophila kikkawai: a study of natural populations from the Indian subcontinent." Genetical Research 71, no. 1 (February 1998): 31–38. http://dx.doi.org/10.1017/s0016672397003054.

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Natural populations of Drosophila kikkawai were collected in India and Sri Lanka, along a latitudinal transect ranging from 6·8° to 31·8° N latitude. Six morphometrical traits were analysed: wing and thorax length, body weight, ovariole number, and abdominal and sternopleural bristle numbers. Significant clines were observed for the three size-related traits and for ovariole number, corresponding to a regular increase in the mean value with latitude, but not for bristle numbers. Due to the utilization of two types of laboratory food, data were distributed into two separate data sets. A low-nutrient food produced smaller flies on average because of more intense crowding. The two rearing conditions produced significant clines but with significantly different slopes. The wing/thorax ratio, which is inversely related to wing loading, also increased with latitude. The analysis of Indian climatic conditions suggested that winter temperature, decreasing from south to north, could be more efficient than summer temperature, which varies in an opposite way, as a selective factor for inducing the clinal variations. The sibling species D. leontia, which is known only from the humid tropics, was found to be much smaller than D. kikkawai and did not fit the clinal regressions. Such morphological differences should help to identify the two species when found in sympatry.

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Piergentili, Roberto. "Multiple Roles of the Y Chromosome in the Biology ofDrosophila melanogaster." Scientific World JOURNAL 10 (2010): 1749–67. http://dx.doi.org/10.1100/tsw.2010.168.

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The X and Y chromosomes ofDrosophila melanogasterwere the first examples of chromosomes associated with genetic information. Thanks to the serendipitous discovery of a male with white eyes in 1910, T.H. Morgan was able to associate the X chromosome of the fruit fly with a phenotypic character (the eye color) for the first time. A few years later, his student, C.B. Bridges, demonstrated that X0 males, although phenotypically normal, are completely sterile. This means that the X chromosome, like the autosomes, harbors genes that control several phenotypic traits, while the Y chromosome is important for male fertility only. Notwithstanding its long history – almost 100 years in terms of genetic studies – most of the features of the Y chromosome are still a mystery. This is due to the intrinsic nature of this genetic element, namely, (1) its molecular composition (mainly transposable elements and satellite DNA), (2) its genetic inertia (lack of recombination due to its heterochromatic nature), (3) the absence of homology with the X (with the only exception of the nucleolar organizer), (4) the lack of visible phenotypes when it is missing (indeed, except for their sterility, X0 flies are normal males), and (5) its low density as for protein-coding sequences (to date, only 13 genes out of approximately 14,000 have been mapped on this chromosome inD. melanogaster, i.e., ~0.1% of the total). Nonetheless, a more accurate analysis reveals that this chromosome can influence several complex phenotypes: (1) it has a role in the fertility of both sexes and viability of males when over-represented; (2) it can unbalance the intracellular nucleotide pool; (3) it can interfere with the gene expression either by recruiting proteins involved in chromatin remodeling (PEV) or, to a higher extent, by influencing the expression of up to 1,000 different genes, probably by changing the availability of transcription factors; (4) it plays a major role (up to 50%) in the resistance to heat-induced male sterility; (5) it affects the behavior; and (6) it plays a role in genetic imprinting. In the present paper, all these Y-related phenotypes are described and a potential similarity with the human Y chromosome is drawn.

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Ready, P. D., J. C. Day, A. A. de Souza, E. F. Rangel, and C. R. Davies. "Mitochondrial DNA characterization of populations of Lutzomyia whitmani (Diptera: Psychodidae) incriminated in the peri-domestic and silvatic transmission of Leishmania species in Brazil." Bulletin of Entomological Research 87, no. 2 (April 1997): 187–95. http://dx.doi.org/10.1017/s0007485300027346.

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AbstractA comparative analysis was performed on 18 mitochondrial DNA sequences, or haplotypes, of Lutzomyia (Nyssomyia) whitmani (Antunes & Coutinho) isolated by PCR from 28 individual flies originating from 10 Brazilian locations 150–2500 km apart. A phylogenetic analysis using maximum parsimony indicated support for three to four major lineages (Outgroups were haplotypes of Lutzomyia (Nyssomyia) intermedia (Lutz & Neiva)). One L. whitmani lineage was found in the Atlantic Forest zone of the North East, including the species' type locality, and is distinct from a second monophyletic group of haplotypes located in the drier interior of Brazil, stretching from the Tropic of Capricorn to Teresina just outside Amazonia. This provides no support for a previous hypothesis that L. whitmani sensu stricto is a single form widely-distributed south of Amazonia, and characterized by derived anthropophilic and synanthropic behavioural traits. The ranges of both lineages include populations incriminated in the peri-domestic transmission of Leishmania braziliensis sensu stricto. A third, Amazonian, group of haplotypes was less well-defined. It appears to consist of two sub-lineages which, like the two Leishmania species associated with them, are strictly silvatic and are separated by the Amazon floodplain. The zoophily of the Amazonian populations was not shown to be an ancestral trait. The geographical distributions of the Brazilian lineages are concordant with the broad patterns of bioclimate believed to have persisted since the late Tertiary period. These findings are part of ongoing research on the behavioural genetics of L. whitmani sensu lato aimed at understanding the evolution and maintenance of peri-domestic transmission of human cutaneous leishmaniasis.

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Flint, J., and T. F. C. Mackay. "Genetic architecture of quantitative traits in mice, flies, and humans." Genome Research 19, no. 5 (May 1, 2009): 723–33. http://dx.doi.org/10.1101/gr.086660.108.

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Lathen, Daniel R., Collin B. Merrill, and Adrian Rothenfluh. "Flying Together: Drosophila as a Tool to Understand the Genetics of Human Alcoholism." International Journal of Molecular Sciences 21, no. 18 (September 11, 2020): 6649. http://dx.doi.org/10.3390/ijms21186649.

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Alcohol use disorder (AUD) exacts an immense toll on individuals, families, and society. Genetic factors determine up to 60% of an individual’s risk of developing problematic alcohol habits. Effective AUD prevention and treatment requires knowledge of the genes that predispose people to alcoholism, play a role in alcohol responses, and/or contribute to the development of addiction. As a highly tractable and translatable genetic and behavioral model organism, Drosophila melanogaster has proven valuable to uncover important genes and mechanistic pathways that have obvious orthologs in humans and that help explain the complexities of addiction. Vinegar flies exhibit remarkably strong face and mechanistic validity as a model for AUDs, permitting many advancements in the quest to understand human genetic involvement in this disease. These advancements occur via approaches that essentially fall into one of two categories: (1) discovering candidate genes via human genome-wide association studies (GWAS), transcriptomics on post-mortem tissue from AUD patients, or relevant physiological connections, then using reverse genetics in flies to validate candidate genes’ roles and investigate their molecular function in the context of alcohol. (2) Utilizing flies to discover candidate genes through unbiased screens, GWAS, quantitative trait locus analyses, transcriptomics, or single-gene studies, then validating their translational role in human genetic surveys. In this review, we highlight the utility of Drosophila as a model for alcoholism by surveying recent advances in our understanding of human AUDs that resulted from these various approaches. We summarize the genes that are conserved in alcohol-related function between humans and flies. We also provide insight into some advantages and limitations of these approaches. Overall, this review demonstrates how Drosophila have and can be used to answer important genetic questions about alcohol addiction.

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Wilkinson, G. S., and M. Taper. "Evolution of genetic variation for condition-dependent traits in stalk-eyed flies." Proceedings of the Royal Society of London. Series B: Biological Sciences 266, no. 1429 (August 22, 1999): 1685–90. http://dx.doi.org/10.1098/rspb.1999.0832.

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Chi, Wanhao, Wei Liu, Wenqin Fu, Shengqian Xia, Ellie S. Heckscher, and Xiaoxi Zhuang. "RNA-binding protein syncrip regulates starvation-induced hyperactivity in adult Drosophila." PLOS Genetics 17, no. 2 (February 22, 2021): e1009396. http://dx.doi.org/10.1371/journal.pgen.1009396.

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How to respond to starvation determines fitness. One prominent behavioral response is increased locomotor activities upon starvation, also known as Starvation-Induced Hyperactivity (SIH). SIH is paradoxical as it promotes food seeking but also increases energy expenditure. Despite its importance in fitness, the genetic contributions to SIH as a behavioral trait remains unexplored. Here, we examined SIH in the Drosophila melanogaster Genetic Reference Panel (DGRP) and performed genome-wide association studies. We identified 23 significant loci, corresponding to 14 genes, significantly associated with SIH in adult Drosophila. Gene enrichment analyses indicated that genes encoding ion channels and mRNA binding proteins (RBPs) were most enriched in SIH. We are especially interested in RBPs because they provide a potential mechanism to quickly change protein expression in response to environmental challenges. Using RNA interference, we validated the role of syp in regulating SIH. syp encodes Syncrip (Syp), an RBP. While ubiquitous knockdown of syp led to semi-lethality in adult flies, adult flies with neuron-specific syp knockdown were viable and exhibited decreased SIH. Using the Temporal and Regional Gene Expression Targeting (TARGET) system, we further confirmed the role of Syp in adult neurons in regulating SIH. To determine how syp is regulated by starvation, we performed RNA-seq using the heads of flies maintained under either food or starvation conditions. RNA-seq analyses revealed that syp was alternatively spliced under starvation while its expression level was unchanged. We further generated an alternatively-spliced-exon-specific knockout (KO) line and found that KO flies showed reduced SIH. Together, this study demonstrates a significant genetic contribution to SIH as a behavioral trait, identifies syp as a SIH gene, and highlights the significance of RBPs and post-transcriptional processes in the brain in regulating behavioral responses to starvation.

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James, Avis C., Ricardo B. R. Azevedo, and Linda Partridge. "Genetic and Environmental Responses to Temperature of Drosophila melanogaster From a Latitudinal Cline." Genetics 146, no. 3 (July 1, 1997): 881–90. http://dx.doi.org/10.1093/genetics/146.3.881.

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Field-collected Drosophila melanogaster from 19 populations in Eastern Australia were measured for body size traits, and the measurements were compared with similar ones on flies from the same populations reared under standard laboratory conditions. Wild caught flies were smaller, and latitudinal trends in size were greater. Reduced size was caused by fewer cells in the wing, and the steeper cline by greater variation in cell area. The reduction in size in field-collected flies may therefore have been caused by reduced nutrition, and the steeper cline may have been caused by an environmental response to latitudinal variation in temperature. No evidence was found for evolution of size traits in response to laboratory culture. The magnitude of phenotypic plasticity in response to temperature of development time, body size, cell size and cell number was examined for six of the populations, to test for latitudinal variation in plasticity. All characters were plastic in response to temperature. Total development time showed no significant latitudinal variation in plasticity, although larval development time showed a marginally significant effect, with most latitudinal variation at intermediate rearing temperatures. Neither thorax length nor wing size and its cellular components showed significant latitudinal variation in plasticity.

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Gompel, Nicolas, and Sean B. Carroll. "Genetic mechanisms and constraints governing the evolution of correlated traits in drosophilid flies." Nature 424, no. 6951 (August 2003): 931–35. http://dx.doi.org/10.1038/nature01787.

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Baker, Richard H., Apurva Narechania, Philip M. Johns, and Gerald S. Wilkinson. "Gene duplication, tissue-specific gene expression and sexual conflict in stalk-eyed flies (Diopsidae)." Philosophical Transactions of the Royal Society B: Biological Sciences 367, no. 1600 (August 19, 2012): 2357–75. http://dx.doi.org/10.1098/rstb.2011.0287.

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Gene duplication provides an essential source of novel genetic material to facilitate rapid morphological evolution. Traits involved in reproduction and sexual dimorphism represent some of the fastest evolving traits in nature, and gene duplication is intricately involved in the origin and evolution of these traits. Here, we review genomic research on stalk-eyed flies (Diopsidae) that has been used to examine the extent of gene duplication and its role in the genetic architecture of sexual dimorphism. Stalk-eyed flies are remarkable because of the elongation of the head into long stalks, with the eyes and antenna laterally displaced at the ends of these stalks. Many species are strongly sexually dimorphic for eyespan, and these flies have become a model system for studying sexual selection. Using both expressed sequence tag and next-generation sequencing, we have established an extensive database of gene expression in the developing eye-antennal imaginal disc, the adult head and testes. Duplicated genes exhibit narrower expression patterns than non-duplicated genes, and the testes, in particular, provide an abundant source of gene duplication. Within somatic tissue, duplicated genes are more likely to be differentially expressed between the sexes, suggesting gene duplication may provide a mechanism for resolving sexual conflict.

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Kumar, Shailesh, Kirklin R. Smith, Yazmin L. Serrano Negron, and Susan T. Harbison. "Short-Term Memory Deficits in the SLEEP Inbred Panel." Clocks & Sleep 1, no. 4 (October 28, 2019): 471–88. http://dx.doi.org/10.3390/clockssleep1040036.

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Although sleep is heritable and conserved across species, sleep duration varies from individual to individual. A shared genetic architecture between sleep duration and other evolutionarily important traits could explain this variability. Learning and memory are critical traits sharing a genetic architecture with sleep. We wanted to know whether learning and memory would be altered in extreme long or short sleepers. We therefore assessed the short-term learning and memory ability of flies from the Sleep Inbred Panel (SIP), a collection of 39 extreme long- and short-sleeping inbred lines of Drosophila. Neither long nor short sleepers had appreciable learning, in contrast to a moderate-sleeping control. We also examined the response of long and short sleepers to enriched social conditions, a paradigm previously shown to induce morphological changes in the brain. While moderate-sleeping control flies had increased daytime sleep and quantifiable increases in brain structures under enriched social conditions, flies of the Sleep Inbred Panel did not display these changes. The SIP thus emerges as an important model for the relationship between sleep and learning and memory.

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CLERGET-DARPOUX, F. "PERFORMING GENETIC ANALYSIS WITH IRREGULAR TRAITS." Clinical Neuropharmacology 15 (1992): 220A—221A. http://dx.doi.org/10.1097/00002826-199201001-00115.

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Rubattu, Speranza. "Genetic Analysis of Complex Cardiovascular Traits." High Blood Pressure & Cardiovascular Prevention 11, no. 1 (2004): 29–33. http://dx.doi.org/10.2165/00151642-200411010-00005.

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Burke, John M., Shunxue Tang, Steven J. Knapp, and Loren H. Rieseberg. "Genetic Analysis of Sunflower Domestication." Genetics 161, no. 3 (July 1, 2002): 1257–67. http://dx.doi.org/10.1093/genetics/161.3.1257.

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Abstract Quantitative trait loci (QTL) controlling phenotypic differences between cultivated sunflower and its wild progenitor were investigated in an F3 mapping population. Composite interval mapping revealed the presence of 78 QTL affecting the 18 quantitative traits of interest, with 2–10 QTL per trait. Each QTL explained 3.0–68.0% of the phenotypic variance, although only 4 (corresponding to 3 of 18 traits) had effects >25%. Overall, 51 of the 78 QTL produced phenotypic effects in the expected direction, and for 13 of 18 traits the majority of QTL had the expected effect. Despite being distributed across 15 of the 17 linkage groups, there was a substantial amount of clustering among QTL controlling different traits. In several cases, regions influencing multiple traits harbored QTL with antagonistic effects, producing a cultivar-like phenotype for some traits and a wild-like phenotype for others. On the basis of the directionality of QTL, strong directional selection for increased achene size appears to have played a central role in sunflower domestication. None of the other traits show similar evidence of selection. The occurrence of numerous wild alleles with cultivar-like effects, combined with the lack of major QTL, suggests that sunflower was readily domesticated.

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Chen, GuoBo, ZhiXiang Zhu, FuTao Zhang, and Jun Zhu. "Quantitative genetic analysis station for the genetic analysis of complex traits." Chinese Science Bulletin 57, no. 21 (April 19, 2012): 2721–26. http://dx.doi.org/10.1007/s11434-012-5108-0.

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Schafer, William R. "Genetic analysis of nicotinic signaling in worms and flies." Journal of Neurobiology 53, no. 4 (November 15, 2002): 535–41. http://dx.doi.org/10.1002/neu.10154.

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Malacrinò, Antonino, Christopher M. Kimber, Martin Brengdahl, and Urban Friberg. "Heightened condition-dependence of the sexual transcriptome as a function of genetic quality in Drosophila melanogaster head tissue." Proceedings of the Royal Society B: Biological Sciences 286, no. 1906 (July 10, 2019): 20190819. http://dx.doi.org/10.1098/rspb.2019.0819.

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Theory suggests sexual traits should show heightened condition-dependent expression. This prediction has been tested extensively in experiments where condition has been manipulated through environmental quality. Condition-dependence as a function of genetic quality has, however, only rarely been addressed, despite its central importance in evolutionary theory. To address the effect of genetic quality on expression of sexual and non-sexual traits, we here compare gene expression in Drosophila melanogaster head tissue between flies with intact genomes (high condition) and flies carrying a major deleterious mutation (low condition). We find that sex-biased genes show heightened condition-dependent expression in both sexes, and that expression in low condition males and females regresses towards a more similar expression profile. As predicted, sex-biased expression was more sensitive to condition in males compared to females, but surprisingly female-biased, rather than male-biased, genes show higher sensitivity to condition in both sexes. Our results thus support the fundamental predictions of the theory of condition-dependence when condition is a function of genetic quality.

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Zimmerman, Erika, Arnar Palsson, and Greg Gibson. "Quantitative Trait Loci Affecting Components of Wing Shape inDrosophila melanogaster." Genetics 155, no. 2 (June 1, 2000): 671–83. http://dx.doi.org/10.1093/genetics/155.2.671.

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AbstractTwo composite multiple regression-interval mapping analyses were performed to identify candidate quantitative trait loci (QTL) affecting components of wing shape in Drosophila melanogaster defined by eight relative warp-based measures. A recombinant inbred line design was used to map QTL for the shape of two intervein regions in the anterior compartment of the wing, using a high resolution map of retrotransposon insertion sites between Oregon-R and Russian 2b. A total of 35 QTL representing up to 23 different loci were identified, many of which are located near components of the epidermal growth factor-Ras signal transduction pathway that regulates vein vs. intervein decision making and vein placement. Over one-half of the loci were detected in both sexes, and just under one-half were detected at two different growth temperatures. Different loci were found to affect aspects of shape in each intervein region, confirming that the shape of the whole wing should be regarded as a compound trait composed of several developmental units. In addition, a reciprocal backcross design was used to map QTL affecting shape in the posterior compartment of the wings of 831 flies, using a molecular map of 16 allele-specific oligohybridization single nucleotide polymorphism (SNP) markers between two divergent inbred lines. A total of 13 QTL were detected and shown to have generally additive effects on separable components of shape, in both sexes. By contrast, 8 QTL that affected wing size in these backcrosses were nearly dominant in their effects. The results confirm at the genetic level that wing shape is regulated independent of wing size and set up the hypothesis that wing shape is regulated in part through the regulation of the length and positioning of wing veins, involving quantitative regulation of the activity of secreted growth factors.

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Vishalakshi, C., and B. N. Singh. "Effect of environmental stress on fluctuating asymmetry in certain morphological traits in Drosophila ananassae: nutrition and larval crowding." Canadian Journal of Zoology 86, no. 5 (May 2008): 427–37. http://dx.doi.org/10.1139/z08-010.

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The association of fluctuating asymmetry and phenotypic and genetic variability with environmental stress was investigated using poor nutrition and larval density as stresses on 10 recently collected isofemale lines of Drosophila ananassae Doleschall, 1858. Trait means for different morphological traits were reduced by stress, whereas phenotypic and genetic variability increased. The levels of fluctuating asymmetry and positional fluctuating asymmetry were similar in flies reared on poor and standard media. In constrast, there is a significant difference in both asymmetry measures in the flies reared at different larval densities for all traits. However, when asymmetry values across all traits were combined into a single index, composite fluctuating asymmetry, significant differences were found in males and females reared at different larval densities but not under nutritional stress. Moreover, composite fluctuating asymmetry is higher in males than in females, suggesting that males are more vulnerable to developmental stress. The results suggest that trait means are more sensitive to stress than fluctuating-symmetry measures and that the effect of stress is trait- and sex-specific. Generalizations based on the use of fluctuating asymmetry as an indicator of environmental stress in D. ananassae should therefore be used with caution.

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Saeboe-Larssen, Stein, and Andrew Lambertsson. "A Novel Drosophila Minute Locus Encodes Ribosomal Protein S13." Genetics 143, no. 2 (June 1, 1996): 877–85. http://dx.doi.org/10.1093/genetics/143.2.877.

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Abstract Minutes comprise >50 phenotypically similar Drosophila mutations believed to affect ribosomal protein genes. Common traits of the Minute phenotype are short and thin bristles, slow development, and recessive lethality. To further investigate the proposed Minute to ribosomal protein correspondence, loss-of-function Minute mutations were induced by P-element mutagenesis. Here, we report a previously undescribed Minute locus that maps to 32A on chromosome 2L; this Minute allele is named P{lac-W}M(2)32A1 and the gene M(2)32A. Flies heterozygous for P{lacW}M(2)32A1 have a medium Minute phenotype. The gene interrupted by the P-element insertion was cloned. Sequence analyses revealed that it encodes the Drosophila homologue of eukaryotic ribosomal protein S13. It is a singlecopy gene and the level of RPS13 transcript is reduced to ~50% in P{lacW}M(2)32A1 heterozygotes. Both transcript level and phenotype are restored to wild type by remobilizing the P element, demonstrating that the mutation is caused by insertion of the P-element construct. These results further strengthen the notion that Minutes encode ribosomal proteins and demonstrate that P-element mutagenesis is a fruitful approach to use in these studies.

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Bryant, Edwin H., Steven A. McCommas, and Lisa M. Combs. "THE EFFECT OF AN EXPERIMENTAL BOTTLENECK UPON QUANTITATIVE GENETIC VARIATION IN THE HOUSEFLY." Genetics 114, no. 4 (December 1, 1986): 1191–211. http://dx.doi.org/10.1093/genetics/114.4.1191.

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ABSTRACT Effects of a population bottleneck (founder-flush cycle) upon quantitative genetic variation of morphometric traits were examined in replicated experimental lines of the housefly founded with one, four or 16 pairs of flies. Heritability and additive genetic variances for eight morphometric traits generally increased as a result of the bottleneck, but the pattern of increase among bottleneck sizes differed among traits. Principal axes of the additive genetic correlation matrix for the control line yielded two suites of traits, one associated with general body size and another set largely independent of body size. In the former set containing five of the traits, additive genetic variance was greatest in the bottleneck size of four pairs, whereas in the latter set of two traits the largest additive genetic variance occurred in the smallest bottleneck size of one pair. One trait exhibited changes in additive genetic variance intermediate between these two major responses. These results were inconsistent with models of additive effects of alleles within loci or of additive effects among loci. An observed decline in viability measures and body size in the bottleneck lines also indicated that there was nonadditivity of allelic effects for these traits. Several possible nonadditive models were explored that increased additive genetic variance as a result of a bottleneck. These included a model with complete dominance, a model with overdominance and a model incorporating multiplicative epistasis.

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Filice, David C. S., and Tristan A. F. Long. "Genetic trade-offs between male reproductive traits in Drosophila melanogaster." Biology Letters 14, no. 10 (October 2018): 20180474. http://dx.doi.org/10.1098/rsbl.2018.0474.

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In Drosophila melanogaster , males engage in both extensive pre- and post-copulatory competition for the opportunity to mate with females and subsequently sire offspring. The selection pressure for increased male reproductive success has resulted in the evolution of a wide diversity of sexual traits. However, despite strong selection, individuals often exhibit considerable phenotypic variation in the expression of these traits, and it is unclear if any of this variation is owing to underlying genetic trade-offs. Here, using hemiclonal flies, we examine how male reproductive success covaries with their ability to induce long-term stimulation of oogenesis and oviposition in their mates, and how this relationship may change over time. We found that males from hemiclone lines with phenotypes that were more successful in a short-term reproductive ‘scramble’ environment were less effective at stimulating long-term fecundity in females. Furthermore, we observed that males from hemiclone lines which showed the most improvement over a longer reproductive interaction period also tended to stimulate higher long-term fecundity in females. Together, these results indicate the presence of genetic trade-offs between different male reproductive traits and offer insights into the maintenance of their variation.

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Gebhardt, M. D., and S. C. Stearns. "Phenotypic plasticity for life-history traits in Drosophila melanogaster. III. Effect of the environment on genetic parameters." Genetical Research 60, no. 2 (October 1992): 87–101. http://dx.doi.org/10.1017/s0016672300030780.

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SummaryWe estimated genetic and environmental variance components for developmental time and dry weight at eclosion in Drosophila melanogaster raised in ten different environments (all combinations of 22, 25 and 28°C and 0·5, 1 and 4% yeast concentration, and 0·25% yeast at 25°C). We used six homozygous lines derived from a natural population for complete diallel crosses in each environment. Additive genetic variances were consistently low for both traits (h2 around 10%). The additive genetic variance of developmental time was larger at lower yeast concentrations, but the heritability did not increase because other components were also larger. The additive genetic effects of the six parental lines changed ranks across environments, suggesting a mechanism for the maintenance of genetic variation in heterogenous environments.The variance due to non-directional dominance was small in most environments. However, there was directional dominance in the form of inbreeding depression for both traits. It was pronounced at high yeast levels and temperatures but disappeared when yeast or temperature were decreased. This meant that the heterozygous flies were more sensitive to environmental differences than homozygous flies. Because dominance effects are not heritable, this suggests that the evolution of plasticity can be constrained when dominance effects are important as a mechanism for plasticity.

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Guingo, Emmanuelle, Yannick Hébert, and Alain Charcosset. "Genetic analysis of root traits in maize." Agronomie 18, no. 3 (1998): 225–35. http://dx.doi.org/10.1051/agro:19980305.

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38

BÖLEK, Yüksel, Hatice ÇOKKIZGIN, and Adem BARDAK. "Genetic Analysis of Fiber Traits in Cotton." Kahramanmaraş Sütçü İmam Üniversitesi Doğa Bilimleri Dergisi 17, no. 1 (November 19, 2014): 15. http://dx.doi.org/10.18016/ksujns.86557.

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Sanford, David A. "Genetic Analysis of Complex Traits Using SAS." Crop Science 45, no. 6 (November 2005): 2674–75. http://dx.doi.org/10.2135/cropsci2005.0013br.

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Kidambi, S. P., T. S. Sandhu, and B. S. Bhullar. "Genetic Analysis of Developmental Traits in Chickpea." Plant Breeding 101, no. 3 (November 1988): 225–35. http://dx.doi.org/10.1111/j.1439-0523.1988.tb00291.x.

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41

Falk, Raphael. "The dominance of traits in genetic analysis." Journal of the History of Biology 24, no. 3 (1991): 457–84. http://dx.doi.org/10.1007/bf00156321.

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42

Hearne, C. "Microsatellites for linkage analysis of genetic traits." Trends in Genetics 8, no. 1 (1992): 288–301. http://dx.doi.org/10.1016/0168-9525(92)90137-s.

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HEARNE, C., S. GHOSH, and J. TODD. "Microsatellites for linkage analysis of genetic traits." Trends in Genetics 8, no. 8 (August 1992): 288–94. http://dx.doi.org/10.1016/0168-9525(92)90256-4.

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Guilfoile, Patrick. "Wrinkled Peas & White-Eyed Fruit Flies: The Molecular Basis of Two Classical Genetic Traits." American Biology Teacher 59, no. 2 (February 1, 1997): 92–95. http://dx.doi.org/10.2307/4450256.

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Dugand, Robert J., J. David Aguirre, Emma Hine, Mark W. Blows, and Katrina McGuigan. "The contribution of mutation and selection to multivariate quantitative genetic variance in an outbred population of Drosophila serrata." Proceedings of the National Academy of Sciences 118, no. 31 (July 29, 2021): e2026217118. http://dx.doi.org/10.1073/pnas.2026217118.

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Genetic variance is not equal for all multivariate combinations of traits. This inequality, in which some combinations of traits have abundant genetic variation while others have very little, biases the rate and direction of multivariate phenotypic evolution. However, we still understand little about what causes genetic variance to differ among trait combinations. Here, we investigate the relative roles of mutation and selection in determining the genetic variance of multivariate phenotypes. We accumulated mutations in an outbred population of Drosophila serrata and analyzed wing shape and size traits for over 35,000 flies to simultaneously estimate the additive genetic and additive mutational (co)variances. This experimental design allowed us to gain insight into the phenotypic effects of mutation as they arise and come under selection in naturally outbred populations. Multivariate phenotypes associated with more (less) genetic variance were also associated with more (less) mutational variance, suggesting that differences in mutational input contribute to differences in genetic variance. However, mutational correlations between traits were stronger than genetic correlations, and most mutational variance was associated with only one multivariate trait combination, while genetic variance was relatively more equal across multivariate traits. Therefore, selection is implicated in breaking down trait covariance and resulting in a different pattern of genetic variance among multivariate combinations of traits than that predicted by mutation and drift. Overall, while low mutational input might slow evolution of some multivariate phenotypes, stabilizing selection appears to reduce the strength of evolutionary bias introduced by pleiotropic mutation.

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Ali, A., K. Javed, I. Zahoor, and K. M. Anjum. "Analysis of non-genetic and genetic influences underlying the growth of Kajli lambs." South African Journal of Animal Science 50, no. 4 (October 29, 2020): 613–25. http://dx.doi.org/10.4314/sajas.v50i4.13.

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Data on 2931 Kajli lambs, born from 2007 to 2018, were used to quantify environmental and genetic effects on growth performance of Kajli sheep. Traits considered for evaluation were birth weight (BWT), 120-day adjusted weight (120DWT), 180-day adjusted weight (180DWT), 270-day adjusted weight (270DWT), and 365-day adjusted weight (365DWT). Fixed effects of year of birth, season of birth, sex, birth type, and dam age on these traits were evaluated using linear procedures of SAS, 9.1. Similarly, BWT, 120DWT, 180DWT, and 270DWT were used as fixed effects mixed model analyses. Variance components, heritability and breeding values were estimated by restricted maximum likelihood. The genetic trend for each trait was obtained by regression of the estimated breeding values (EBV) on year of birth. Analyses revealed substantial influence of birth year on all traits. Sex and birth type were the significant sources of variation for BWT and 120DWT. Season of birth did not influence birth weight meaningfully, but had a significant role in the expression of 120DWT, 180DWT, and 270DWT. Heritability estimates were generally low (0.003 ± 0.018 to 0.099 ± 0.067) for all traits. With the exception of the genetic correlation of 180DWT and 365DWT, the genetic correlations between trait were strong and positive. Only 365DWT had a positive genetic trend. Although the heritability estimates for almost all weight traits were low, high and positive genetic correlations between BWT and other weight traits suggest that selection based on BWT would result in the improvement of other weight traits as a correlated response.Keywords: bodyweight, breeding value, genetic correlation, sheep

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Kenig, Bojan, Aleksandra Patenkovic, Marko Andjelkovic, and Marina Stamenkovic-Rada. "Life-history variation of drosophila subobscura under lead pollution depends on population history." Genetika 46, no. 3 (2014): 693–703. http://dx.doi.org/10.2298/gensr1403693k.

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Contamination represents environmental stress that can affect genetic variability of populations, thus influencing the evolutionary processes. In this study, we evaluate the relationship between heavy metal contamination (Pb) and phenotypic variation, assessed by coefficients of variation (CV) of life-history traits. To investigate the consequences of population origin on variation of life history traits in Drosophila subobscura in response to different laboratory conditions we compared populations from relatively polluted and unpolluted environments. Prior to experiment, flies from natural populations were reared for two generations in standard Drosophila laboratory conditions. Afterwards, all flies were cultured on three different media: one medium without lead as the control, and the other two with different concentrations of lead. Coefficients of variation (CV) of life- history traits (fecundity, egg-to-adult viability and developmental time) were analyzed on flies sampled in generations F2, F5 and F8 from these three groups. In later generations samples from both polluted and unpolluted environments showed the increased fecundity variation on media with lead. This increase is expressed more in population from unpolluted environment. On contrary, population from unpolluted environment had increased variation of developmental time in earlier, F2 generation, compared to the population from polluted environment. Our results showed that the response to heavy metal contamination depends on the evolutionary history of the populations regarding habitat pollution.

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Casas, Eduard, and Tanya Vavouri. "Mechanisms of epigenetic inheritance of variable traits through the germline." Reproduction 159, no. 6 (June 2020): R251—R263. http://dx.doi.org/10.1530/rep-19-0340.

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During the past half century, evidence for inheritance of variable traits has accumulated from experiments in plants and animals and epidemiological studies in humans. Here, we summarize some of the reported cases of epigenetic inheritance and the proposed mechanisms involved in the transmission of non-genetic information between generations in plants, nematodes, flies and mammals. It has long been accepted that information is epigenetically inherited in plants. Although many questions regarding the underlying mechanisms remain to be answered, it is now evident that epigenetic mechanisms are also responsible for the transmission of phenotypes in animals. We highlight similarities and differences between models and species.

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Joshi, Anjali, Anil Kumar, Vartika Budhlakoti, and Nidhi Bhatt. "Genetic Analysis of Quality Traits in Bread Wheat." International Journal of Current Microbiology and Applied Sciences 9, no. 2 (February 10, 2020): 929–38. http://dx.doi.org/10.20546/ijcmas.2020.902.110.

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Kimura, Tetsuaki, Atsuko Shimada, Noriyoshi Sakai, Hiroshi Mitani, Kiyoshi Naruse, Hiroyuki Takeda, Hidetoshi Inoko, Gen Tamiya, and Minori Shinya. "Genetic Analysis of Craniofacial Traits in the Medaka." Genetics 177, no. 4 (December 2007): 2379–88. http://dx.doi.org/10.1534/genetics.106.068460.

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Journal articles on the topic 'Genetic analysis; Flies; Traits'

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