Biochemical and regulatory interactions central to biological networks are expected to cause extensive genetic interactions or epistasis affecting the heritability of complex traits and the distribution of genotypes in populations. However, the inference of epistasis from the observed phenotype-genotype correlation is impeded by statistical difficulties, while the theoretical understanding of t...

Because DSM-IV cocaine dependence (CD) is heterogeneous, it is not an optimal phenotype to identify genetic variation contributing to risk for cocaine use and related behaviors (CRBs). We used a cluster analytic method to differentiate homogeneous, highly heritable subtypes of CRBs and to compare their utility with that of the DSM-IV CD as traits for genetic association analysis. Clinical featu...

The advent of cheaply available high-throughput genetic and genomic techniques has equipped animal geneticists with an unprecedented ability to generate massive amounts of molecular data. As a result, large lists of genes differentially expressed in many experimental conditions of interests have been reported and, likewise, the association of an evergrowing number of DNA variants with phenotype...

Breeding programs in oriental river prawn populations would benefit from a knowledge of heritabilities for growth-related traits to assess their potential genetic improvement. This study reports the results heritability estimation and evaluation epistatic interactions (Macrobrachium nipponense). The showed that estimates (h2) were low medium magnitude, ranging between 0.10 (±0.02) 0.22 (±0.01) ...

It has been suggested that traits associated with fitness, such as fertility, may have proportionately more genetic variation arising from non-additive effects than traits with higher heritability, such as milk yield. Here, we performed a large genome scan with 408,255 single nucleotide polymorphism (SNP) markers to identify chromosomal regions associated with dominance and epistatic (pairwise ...

Crossbreeding effects for wool quality traits viz. greasy fleece weight (kg), staple length (cm), average fibre diameter (μ) and medulation percentage were estimated using the Dickerson’s and Kinghorn’s models. The data analyzed involved 15 genetic groups including Nali purebred, F1’s of two and three breeds, F2’s and reciprocal crossbred obtained from the crossing of Nali (N), Merino (M) and C...

The genetic control of root weight, root volume and root to shoot weight ratio was studied in peas (Pisum sativum L.) at flowering. The four populations used were developed from crosses between lines and cultivars differing in size of the root systems. Plants of the F 1, F 2 , backcross and parental generations were evaluated in pots filled with soil: sand mixture, in a completely randomized de...

Maps of genetic interactions can dissect functional redundancies in cellular networks. Gene expression profiles as high-dimensional molecular readouts of combinatorial perturbations provide a detailed view of genetic interactions, but can be hard to interpret if different gene sets respond in different ways (called mixed epistasis). Here we test the hypothesis that mixed epistasis between a gen...

Understanding the genetic basis of complex quantitative traits is a central problem in evolutionary biology, particularly for traits that may lead to adaptations in natural populations. The annual and perennial ecotypes of Mimulus guttatus provide an excellent experimental system for characterizing the genetic components of population divergence. The 2 life history ecotypes coexist throughout t...

Lupus is a prototypic systemic autoimmune disease that has a significant genetic component in its etiology. Several genome-wide screens have identified multiple loci that contribute to disease susceptibility in lupus-prone mice, including the Fas-deficient MRL/Fas(lpr) strain, with each locus contributing in a threshold liability manner. The centromeric region of chromosome 7 was identified as ...