A new mixed-model method was developed for mapping quantitative trait loci (QTL) by incorporating multiple polygenic covariance structures. First, we used genome-wide markers to calculate six different kinship matrices. We then partitioned the total genetic variance into six variance components, one corresponding to each kinship matrix, including the additive, dominance, additive × additive, do...

The relative proportion of additive and non-additive variation for complex traits is important in evolutionary biology, medicine, and agriculture. We address a long-standing controversy and paradox about the contribution of non-additive genetic variation, namely that knowledge about biological pathways and gene networks imply that epistasis is important. Yet empirical data across a range of tra...

(co) variance components and genetic parameters for growth traits in arman sheep were estimated, using data collected during an 11-year period (1999-2010), by applying the restricted maximum likelihood (reml) procedure under univariate and bivariate animal models. the studied traits were body weight of lamb at birth (bw), body weight at 3 months of age as weaning weight (ww), body weight at 6 m...

We measured the additive genetic variance within populations and the composite additive, dominance, and epistatic effects contributing to differentiation of photoperiodic response between two southern (ancestral) and each of four progressively more northern (derived) populations of the pitcher-plant mosquito, Wyeomyia smithii. Critical photoperiod and its additive genetic variance but not its h...

A genetic map containing 103 microsatellite loci and 200 F2 plants derived from the cross R15 × Ye478 were used for mapping of quantitative trait loci (QTL) in maize (Zea mays L.). QTLs were characterized in a population of 200 F2:4 lines, derived from selfing the F2 plants, and were evaluated with two replications in two environments. QTL mapping analysis of plant height was performed by using...

In clonally propagated crops, non-additive genetic effects can be effectively exploited by the identification of superior genetic individuals as varieties. Cassava (Manihot esculenta Crantz) is a clonally propagated staple food crop that feeds hundreds of millions. We quantified the amount and nature of non-additive genetic variation for three key traits in a breeding population of cassava from...

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 siz...

determining general and specific combining ability of lines is necessary to use them as parents of hybrid varieties. in addition, estimates of the heritability of characters helps in selecting suitable breeding methods and predicting genetic gains of the traits. to determine general and specific combining abilities and gene effects of agronomic characters, five cms lines and four restorer lines...