Epistatic interactions can frustrate and shape evolutionary change 1,2 . Indeed, phenotypes may fail to evolve because essential mutations can only be selected positively if fixed simultaneously . How environmental variability affects such constraints is poorly understood. Here we studied genetic constraints in fixed and fluctuating environments, using the Escherichia coli lac operon as a model...

Twin and adoption studies consistently implicate the importance of genetic influences on alcoholism risk, especially in men. Heritability estimates suggest that approximately 50% to 60% of the variability in alcoholism liability is associated with genetic factors. Although there has been progress in identifying specific genes that predispose toward alcoholism, we know relatively little about th...

Adjustment factors for age and month of calving were developed from Holstein lactation m r d s in Ecuador. Age factors were similar to those in the United States, but calendar month effects were small, apparently because of uniform feeding and management as the result of a similar climate throughout the year. Genetic evaluations were computed with the USDA animal model system but without identi...

There is now strong evidence that general intelligence as measured by ability tests is largely genetically determined, in western white societies at least (Eaves, 1975). The evidence for educational achievement is more conflicting and several studies have found lower heritabilities in school tests and examinations. In this study we analyse the results of a sample of monozygotic (MZ) and dizygot...

Genomic tools allow the study of the whole genome, and facilitate the study of genotypeenvironment combinations and their relationship with phenotype. However, most genomic prediction models developed so far are appropriate for Gaussian phenotypes. For this reason, appropriate genomic prediction models are needed for count data, since the conventional regression models used on count data with a...

in the present study, the binding isotherms for interaction of a homologous series of n-alkyltrimethyl ammonium bromides with bovine serum albumin (bsa) have been analyzed on basis of intrinsic thermodynamic quantities. in this regards, the intrinsic gibbs free energy of binding, agb(i,)„ has been estimated at various surfactant concentrations and its trend of variation for both binding sets ha...