Jobran Chebib and Frédéric GuillaumePlease use the format "First name initials family name" as in "Marie S. Curie, Niels H. D. Bohr, Albert Einstein, John R. R. Tolkien, Donna T. Strickland"
<p>Genetic correlations between traits may cause correlated responses to selection depending on the source of those genetic dependencies. Previous models described the conditions under which genetic correlations were expected to be maintained. Selection, mutation and migration are all proposed to have similar effects on genetic correlation, regardless of whether the underlying genetic architecture consists of pleiotropic or tightly-linked loci affecting the traits. Here, we investigate the conditions under which pleiotropy and linkage have differential effects on the genetic correlations between traits by explicitly modeling multiple genetic architectures to look at the effects of selection strength, degree of correlational selection, mutation rate, mutational variance, recombination rate, and migration rate. We show that at mutation-selection(-migration) balance, mutation rates differentially affect the equilibrium levels of genetic correlation when architectures are composed of pairs of physically linked loci compared to architectures of pleiotropic loci. Even when there is perfect linkage (no recombination within pairs of linked loci), a lower genetic correlation is maintained than with pleiotropy, with a lower mutation rate leading to a larger decrease. These results imply that the detection of causal loci in multi-trait association studies will be affected by the type of underlying architectures, whereby pleiotropic variants are more likely to be underlying multiple detected associations. We also confirm that tighter linkage between non-pleiotropic causal loci maintains higher genetic correlations at the traits and leads to a greater proportion of false positives in association analyses.</p>
pleiotropy, linkage, mutation, GWAS, genotype-phenotype map, genetics, quantitative traits
Bioinformatics & Computational Biology, Evolutionary Applications, Evolutionary Dynamics, Evolutionary Theory, Genome Evolution, Genotype-Phenotype, Molecular Evolution, Population Genetics / Genomics, Quantitative Genetics