The Genetic Architecture of Quantitative Traits Cannot Be Inferred from Variance Component Analysis

Classical quantitative genetic analyses estimate additive and non-additive genetic and environmental components of variance from phenotypes of related individuals without knowing the identities of quantitative trait loci (qtls). many studies have found a large proportion of quantitative trait variation can be attributed to the additive genetic variance (va),providing the basis for claims that non-additive gene actions are unimportant. in this study,we show that arbitrarily defined parameterizations of genetic effects seemingly consistent with non-additive gene actions can also capture the majority of genetic variation. this reveals a logical flaw in using the relative magnitudes of variance components to indicate the relative importance of additive and non-additive gene actions. we discuss the implications and propose that variance component analyses should not be used to infer the genetic architecture of quantitative traits. © 2016 huang,mackay.