the choice of an efficient breeding procedure depends to a large extent on knowledge of the genetic system controlling the character to be selected. the objective of this study was to determine genetic parameters for yield and other traits including some of the yield components under three planting densities, using analysis of generation means (p1, p2, f1, f2, bc1 and bc2) derived from crosses ...

combining ability, gene action, heritability and other genetic parameters in bread wheat under drought stress condition were evaluated using half diallel design. nine wheat cultivars and 36 derived f1 assessed in a randomized complete block design with three replications in shahid bahonar university of kerman research field in 2013. evaluated genotypes showed high diversity for all traits. gene...

Epistasis refers to the nonadditive interactions between genes in determining phenotypes. Considerable efforts have shown that, even for a given organism, epistasis may vary both in intensity and sign. Recent comparative studies supported that the overall sign of epistasis switches from positive to negative as the complexity of an organism increases, and it has been hypothesized that this chang...

Abstract Epistasis can be defined as the statistical interaction of genes during expression a phenotype. It is believed that it plays fundamental role in gene expression, individual genetic variants have reported very small increase disease risk previous Genome-Wide Association Studies. The most successful approach to epistasis detection exhaustive method, although its exponential time complexi...

Epistasis between mutations in two genes is thought to reflect an interdependence of their functions. While sometimes epistasis is predictable using mechanistic models, its roots seem, in general, hidden in the complex architecture of biological networks. Here, we ask how epistasis can be quantified based on the mathematical dependence of a system-level trait (e.g. fitness) on lower-level trait...

Bonhoeffer et al. (Reports, 26 November 2004, p. 1547) presented evidence for positive epistasis in a clinical data set of HIV-1 mutants and corresponding fitness values. We demonstrate that biases in the original and simulated data sets may lead to erroneous evidence for epistasis. More rigorous statistical tests must be used to account for such biases before one can infer epistasis.

How, and to what extent, does the environment influence the way mutations interact? Do environmental changes affect both the sign and the magnitude of epistasis? Are there any correlations between environments in the variability, sign or magnitude of epistasis? Very few studies have tackled these questions. Here, we addressed them in the context of viral emergence. Most emerging viruses are RNA...