Medical Biochemistry and Biophysics Seminar Series, autumn 2012
Örjan Carlborg, Dept. of Clinical Sciences, Division of Computational Genetics, Swedish University of Agricultural Sciences, Uppsala, Sweden
"Understanding the genetic architecture of complex traits"
Place: lecture hall KB3A9, Lilla hörsalen, KBC
Host: Andrei Chabes
Abstract Understanding how genes contribute to the phenotypic variability observed in populations is a major challenge in biology. A common approach to dissect the genetics of complex traits is to measure the genotype of individuals in a population at a large number of loci across the genome and then evaluate whether the phenotypic mean differs between the individuals that carry particular combinations of genetic variants, alleles, at either individual loci (i.e. detection of additive, dominance and epigenetic effects of loci) or at multiple loci (i.e. to detect genetic interactions or epistasis). I will here give a brief introduction to this topic and illustrate the insights that can be gained into the genetics of complex traits using these approaches by using examples from our research in domestic animals. An alternative, and promising, strategy to identify genes involved in gene-by-gene or gene-by-environment interactions is to search for loci that causes a difference in variance (a variance heterogeneity) between genotypes. This talk will be concluded by presenting some recent work to develop theory and tools for genome-wide mapping of individual variance-controlling loci. Empirical findings from studies of data in Arabidopsis thaliana and Saccharomyces cerevisiae will be used to illustrate the contribution of such loci to the genetic architecture of complex traits and the implications of the findings on our understanding of the genetic regulation of complex trait variation.