Faculty Opinions recommendation of Plastic responses to novel environments are biased towards phenotype dimensions with high additive genetic variation.

2019 ◽  
Author(s):  
Luis-Miguel Chevin
Keyword(s):  
Genetic Variation ◽  
Additive Genetic Variation ◽  
Novel Environments ◽  
Plastic Responses

scholarly journals Plastic responses to novel environments are biased towards phenotype dimensions with high additive genetic variation

2019 ◽  
Vol 116 (27) ◽  
pp. 13452-13461 ◽  
Author(s):  
Daniel W. A. Noble ◽  
Reinder Radersma ◽  
Tobias Uller
Keyword(s):  
Genetic Variation ◽  
Meta Analysis ◽  
Additive Genetic Variance ◽  
Genetic Mutation ◽  
Developmental Systems ◽  
Additive Genetic Variation ◽  
Genetic Constraint ◽  
Novel Environments ◽  
Plastic Responses

Environmentally induced phenotypes have been proposed to initiate and bias adaptive evolutionary change toward particular directions. The potential for this to happen depends in part on how well plastic responses are aligned with the additive genetic variance and covariance in traits. Using meta-analysis, we demonstrate that plastic responses to novel environments tend to occur along phenotype dimensions that harbor substantial amounts of additive genetic variation. This suggests that selection for or against environmentally induced phenotypes typically will be effective. One interpretation of the alignment between the direction of plasticity and the main axis of additive genetic variation is that developmental systems tend to respond to environmental novelty as they do to genetic mutation. This makes it challenging to distinguish if the direction of evolution is biased by plasticity or genetic “constraint.” Our results therefore highlight a need for new theoretical and empirical approaches to address the role of plasticity in evolution.

scholarly journals Quantifying multivariate genotype-by-environment interactions, evolutionary potential and its context-dependence in natural populations of the water flea, Daphnia magna

2020 ◽  
Author(s):  
Franziska S. Brunner ◽  
Alan Reynolds ◽  
Ian W. Wilson ◽  
Stephen Price ◽  
Steve Paterson ◽  
...  
Keyword(s):  
Genetic Variation ◽  
Daphnia Magna ◽  
Natural Populations ◽  
Thermal Adaptation ◽  
Plastic Response ◽  
Evolutionary Potential ◽  
Genotype By Environment Interactions ◽  
Additive Genetic Variation ◽  
Genotype By Environment ◽  
Plastic Responses

ABSTRACTGenotype-by-environment interactions (G x E) underpin the evolution of plastic responses in natural populations. Theory assumes that G x E interactions exist but empirical evidence from natural populations is equivocal and difficult to interpret because G x E interactions are normally univariate plastic responses to a single environmental gradient. We compared multivariate plastic responses of 43 Daphnia magna clones from the same population in a factorial experiment that crossed temperature and food environments. Multivariate plastic responses explained more than 30% of the total phenotypic variation in each environment. G x E interactions were detected in most environment combinations irrespective of the methodology used. However, the nature of G x E interactions was context-dependent and led to environment-specific differences in additive genetic variation (G-matrices). Clones that deviated from the population average plastic response were not the same in each environmental context and there was no difference in whether clones varied in the nature (phenotypic integration) or magnitude of their plastic response in different environments. Plastic responses to food were aligned with additive genetic variation (gmax) at both temperatures, whereas plastic responses to temperature were not aligned with additive genetic variation (gmax) in either food environment. These results suggest that fundamental differences may exist in the potential for our population to evolve novel responses to food versus temperature changes, and challenges past interpretations of thermal adaptation based on univariate studies.

scholarly journals Hidden genetic variation in plasticity increases the potential to adapt to novel environments

2020 ◽  
Author(s):  
Greg M. Walter ◽  
James Clark ◽  
Delia Terranova ◽  
Salvatore Cozzolino ◽  
Antonia Cristaudo ◽  
...  
Keyword(s):  
Genetic Variation ◽  
Genetic Variance ◽  
Adaptive Plasticity ◽  
The Novel ◽  
Rapid Adaptation ◽  
Novel Environment ◽  
Slow Adaptation ◽  
Novel Environments ◽  
Plastic Responses ◽  
Native Site

AbstractAdaptive plasticity increases population persistence, but can slow adaptation to changing environments by hiding the effects of different alleles on fitness. However, if plastic responses are no longer adaptive in novel environments, then differences among alleles can emerge and increase genetic variation in fitness that allows rapid adaptation. We tested this hypothesis by transplanting cuttings and seeds of a Sicilian daisy within and outside its native range, and quantifying variation in morphology, physiology, gene expression and fitness. We show that genetic variance in plasticity increases the potential for rapid adaptation to novel environments. Genetic variation in fitness was low across native environments where plasticity effectively tracked familiar environments. In the novel environment however, genetic variation in fitness increased threefold, and correlated with genetic variation in plasticity. Furthermore, genetic variation that can increase fitness in the novel environment had the lowest fitness at the native site, suggesting that adaptation to novel environments relies on genetic variation in plasticity that is selected against in native environments.

scholarly journals Pleiotropy and multilocus polymorphisms.

Genetics ◽  
1992 ◽  
Vol 130 (1) ◽  
pp. 223-227
Author(s):  
A Gimelfarb
Keyword(s):  
Genetic Variation ◽  
Linkage Disequilibrium ◽  
Stabilizing Selection ◽  
Additive Genetic Variation ◽  
Very High

Abstract It is demonstrated that systems of two pleiotropically related characters controlled by additive diallelic loci can maintain under Gaussian stabilizing selection a stable polymorphism in more than two loci. It is also shown that such systems may have multiple stable polymorphic equilibria. Stabilizing selection generates negative linkage disequilibrium, as a result of which the equilibrium phenotypic variances are quite low, even though the level of allelic polymorphisms can be very high. Consequently, large amounts of additive genetic variation can be hidden in populations at equilibrium under stabilizing selection on pleiotropically related characters.

scholarly journals Characterizing the oligogenic architecture of plant growth phenotypes informs genomic selection approaches in a common wheat population

BMC Genomics ◽  
2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Noah DeWitt ◽  
Mohammed Guedira ◽  
Edwin Lauer ◽  
J. Paul Murphy ◽  
David Marshall ◽  
...  
Keyword(s):  
Genetic Variation ◽  
Plant Growth ◽  
Genomic Selection ◽  
Plant Height ◽  
Prediction Models ◽  
Growth Traits ◽  
Heading Date ◽  
Additive Genetic Variation ◽  
Moderate Effect ◽  
Over Time

Abstract Background Genetic variation in growth over the course of the season is a major source of grain yield variation in wheat, and for this reason variants controlling heading date and plant height are among the best-characterized in wheat genetics. While the major variants for these traits have been cloned, the importance of these variants in contributing to genetic variation for plant growth over time is not fully understood. Here we develop a biparental population segregating for major variants for both plant height and flowering time to characterize the genetic architecture of the traits and identify additional novel QTL. Results We find that additive genetic variation for both traits is almost entirely associated with major and moderate-effect QTL, including four novel heading date QTL and four novel plant height QTL. FT2 and Vrn-A3 are proposed as candidate genes underlying QTL on chromosomes 3A and 7A, while Rht8 is mapped to chromosome 2D. These mapped QTL also underlie genetic variation in a longitudinal analysis of plant growth over time. The oligogenic architecture of these traits is further demonstrated by the superior trait prediction accuracy of QTL-based prediction models compared to polygenic genomic selection models. Conclusions In a population constructed from two modern wheat cultivars adapted to the southeast U.S., almost all additive genetic variation in plant growth traits is associated with known major variants or novel moderate-effect QTL. Major transgressive segregation was observed in this population despite the similar plant height and heading date characters of the parental lines. This segregation is being driven primarily by a small number of mapped QTL, instead of by many small-effect, undetected QTL. As most breeding populations in the southeast U.S. segregate for known QTL for these traits, genetic variation in plant height and heading date in these populations likely emerges from similar combinations of major and moderate effect QTL. We can make more accurate and cost-effective prediction models by targeted genotyping of key SNPs.

scholarly journals Mhc polymorphisms fail to explain the heritability of phytohaemagglutinin-induced skin swelling in a wild passerine

2009 ◽  
Vol 5 (6) ◽  
pp. 784-787 ◽  
Author(s):  
Camille Bonneaud ◽  
Janet S. Sinsheimer ◽  
Murielle Richard ◽  
Olivier Chastel ◽  
Gabriele Sorci
Keyword(s):  
Genetic Variation ◽  
Immune Responses ◽  
Environmental Effects ◽  
Natural Populations ◽  
Wild Populations ◽  
Genetic Determinants ◽  
House Sparrows ◽  
Additive Genetic Variation ◽  
Significant Heritability ◽  
Mhc Polymorphisms

Genetic estimates of the variability of immune responses are rarely examined in natural populations because of confounding environmental effects. As a result, and because of the difficulty of pinpointing the genetic determinants of immunity, no study has to our knowledge examined the contribution of specific genes to the heritability of an immune response in wild populations. We cross-fostered nestling house sparrows to disrupt the association between genetic and environmental effects and determine the heritability of the response to a classic immunological test, the phytohaemagglutinin (PHA)-induced skin swelling. We detected significant heritability estimates of the response to PHA, of body mass and tarsus length when nestlings were 5 and 10 days old. Variation at Mhc genes, however, did not explain a significant portion of the genetic variation of nestling swelling to PHA. Our results suggest that while PHA-induced swelling is influenced by the nest of origin, the importance of additive genetic variation relative to non-additive genetic variation and the genetic factors that influence the former in wild populations still need to be identified for this trait.

scholarly journals Shared additive genetic variation for alcohol dependence among subjects of African and European ancestry

2017 ◽  
Vol 24 (1) ◽  
pp. 132-144 ◽  
Author(s):  
Leslie A. Brick ◽  
Matthew C. Keller ◽  
Valerie S. Knopik ◽  
John E. McGeary ◽  
Rohan H.C. Palmer
Keyword(s):  
Genetic Variation ◽  
Alcohol Dependence ◽  
European Ancestry ◽  
Additive Genetic Variation

Utilization of heterosis in poultry

1958 ◽  
Vol 9 (4) ◽  
pp. 599 ◽  
Author(s):  
FHW Morley
Keyword(s):  
Body Weight ◽  
Genetic Variation ◽  
Genetic Variability ◽  
Sex Chromosome ◽  
Inbred Lines ◽  
White Leghorn ◽  
Egg Weight ◽  
Additive Genetic Variation ◽  
White Leghorns ◽  
Recessive Genes

Records were analysed of 500-day production, egg weight, 11-week and mature body weight, sex maturity, and broodiness of the crossbred progeny of inbred lines of Australorps mated to White Leghorns, and inbred lines of White Leghorns mated to Australorps. Clear differences between lines of both breeds mere found in most characters, indicating the presence of potentially useful amounts of additive genetic variation. Non-additive genetic variation was also found to be present in varying degrees in different characters. Because of the difficulties of developing and maintaining inbred stocks of poultry, and the importance of sex-linked characteristics in some commercial environments, a scheme is proposed which may enable heterosis to be exploited without the use of inbred material. The basis of this scheme is the combination of the White Leghorn sex chromosome, with varying proportions of Australorp and White Leghorn autosomes, in a new breed. Assuming that the heterosis observed in the F1 is due to elimination of certain biochemical blocks determined by recessive genes, the formation of the new breed should enable the methods of closed flock breeding to be used in material at a higher level of production, and likely to contain more genetic variability, than either parent breed.

Sign in / Sign up

Export Citation Format

Share Document