Predicting and observing the properties of second cycle hybrids using basic generations and inbred line × F1 crosses

Pooni, H S; Jinks, J L; Toledo, J.F.

doi:10.1038/hdy.1985.16

Cited by 7 publications

(2 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…My study can be added to a growing body of evidence (e.g., Jinks and Perkins 1969;Pooni et al 1985;Macnair and Cumbes 1989;Hard et al 1992Hard et al , 1993Cabot et al 1994;Davis et al 1994;Lai et al 1994;Long et al 1995;Mckay 1995) demonstrating that many characters do not fit a simple additive model. The implications of this finding are less clear: though these effects are significant in statistical models, their biological significance remains poorly understood.…”

Section: Implications For the Genetics Of Adaptation And Speciationmentioning

confidence: 91%

Genetic Divergence in Adaptive Characters Between Sympatric Species of Stickleback

Hatfield

1997

The American Naturalist

108

View full text Add to dashboard Cite

This study explored the genetic basis of phenotypic differences between two sympatric species of ecologically and morphologically divergent sticklebacks (Gasterosteus aculeatus complex). The aim was to understand how many loci determine the differences and to what extent the differences are due to additive or nonadditive gene action. I reared the two parental species, F1 and F2 hybrids, and both backcrosses in the laboratory and measured the following quantitative characters: gill raker number and length (both involved in feeding), lateral plate number and pelvic spine length (both involved in predator defense), and growth (a fitness component). I then applied joint-scaling regression models to estimate composite additive, dominance and epistatic effects, and their contribution to divergence of parental lines. A simple additive model was sufficient for gill raker number and growth; additive and dominance effects contributed significantly to divergence in plate number and pelvic spine length; and additive, dominance, and epistatic effects contributed significantly to divergence in gill raker length. Wright's estimator for the number of loci for the four morphological characters ranged from 1 to 50. My results suggest that adaptive divergence between limnetic and benthic sticklebacks has taken place through a variety of genetic mechanisms specific to different traits. Though interspecific hybrids are completely fertile and viable in the laboratory, they are selected against in the wild. The pattern of inheritance for the traits examined here directly influences how well hybrids can exploit the two major resource environments in the wild.

show abstract

Section: Implications For the Genetics Of Adaptation And Speciationmentioning

confidence: 91%

Genetic Divergence in Adaptive Characters Between Sympatric Species of Stickleback

Hatfield

1997

The American Naturalist

108

View full text Add to dashboard Cite

show abstract

“…Identifying the genetic architecture underlying traits is a central goal of evolutionary biologists (Demuth, Flanagan, & Delph, ; Fuchsberger et al., ; Kitano et al., ; Küpper et al., ), as well as animal and plant breeders (Gall, ; Pooni, Jinks, & de Toledo, ; Singh, Bhullar, & Gill, ). The genetic architecture of a trait may, at its simplest, be described by the action of a single locus whose effect can be decomposed into additive and dominance components.…”

Section: Introductionmentioning

confidence: 99%

Inferring the potentially complex genetic architectures of adaptation, sexual dimorphism and genotype by environment interactions by partitioning of mean phenotypes

Armstrong

Anderson

Blackmon

2019

J of Evolutionary Biology

View full text Add to dashboard Cite

Genetic architecture fundamentally affects the way that traits evolve. However, the mapping of genotype to phenotype includes complex interactions with the environment or even the sex of an organism that can modulate the expressed phenotype.Line-cross analysis is a powerful quantitative genetics method to infer genetic architecture by analysing the mean phenotype value of two diverged strains and a series of subsequent crosses and backcrosses. However, it has been difficult to account for complex interactions with the environment or sex within this framework. We have developed extensions to line-cross analysis that allow for gene by environment and gene by sex interactions. Using extensive simulation studies and reanalysis of empirical data, we show that our approach can account for both unintended environmental variation when crosses cannot be reared in a common garden and can be used to test for the presence of gene by environment or gene by sex interactions. In analyses that fail to account for environmental variation between crosses, we find that line-cross analysis has low power and high false-positive rates. However, we illustrate that accounting for environmental variation allows for the inference of adaptive divergence, and that accounting for sex differences in phenotypes allows practitioners to infer the genetic architecture of sexual dimorphism. K E Y W O R D Senvironmental effect, epistasis, G × E, line-cross analysis, sexual dimorphism

show abstract

Predicting the potential of open-pollinating populations for the production of superior F1 hybrids

Toledo

Filho

1985

Theoret. Appl. Genetics

View full text Add to dashboard Cite

The distributive properties of a single population or of a population resulting from a cross between two populations are reproduced when inbreds randomly extracted from the population itself or from the two parental populations are randomly paired. Hence, population parameters that are usually obtained during a breeding programme can be used to predict the performance of the F1 hybrids that can be derived from them at that stage. Multiple allelism, epistasis and deviations from Hardy-Weinberg equilibria should not cause biasis to the predictions. While in theory genotype x environment interaction and linkage disequilibrium may disturb the predictions, in practice they are unlikely to create problems that cannot be accommodated. Genotypic and phenotypic predictions of the proportions of the F1 hybrid distribution scoring above or below a given standard are made and analysed for three characters, weight of the ears, plant height and height of the ear, in two populations of maize per se and their interpopulational cross. Because no random inbred lines from the experimental populations are presently available we cannot check our predictions. However, genotypic and phenotypic predictions and observations of F1 hybrids obtained from populations created by computer simulation are provided to illustrate our procedures.

show abstract

Predicting and observing the properties of second cycle hybrids using basic generations and inbred line × F1 crosses

Cited by 7 publications

References 18 publications

Genetic Divergence in Adaptive Characters Between Sympatric Species of Stickleback

Genetic Divergence in Adaptive Characters Between Sympatric Species of Stickleback

Inferring the potentially complex genetic architectures of adaptation, sexual dimorphism and genotype by environment interactions by partitioning of mean phenotypes

Predicting the potential of open-pollinating populations for the production of superior F1 hybrids

Contact Info

Product

Resources

About