Open AccessAn Epistatic Genetic Basis for Physical Activity Traits in Mice
Author(s) -
Larry J. Leamy,
Daniel Pomp,
J. Timothy Lightfoot
Publication year - 2008
Publication title -
journal of heredity
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 92
eISSN - 1471-8505
pISSN - 0022-1503
DOI - 10.1093/jhered/esn045
Subject(s) - epistasis , quantitative trait locus , biology , genetic architecture , genetics , population , locus (genetics) , genetic variation , trait , inbred strain , evolutionary biology , gene , candidate gene , genome scan , allele , microsatellite , demography , sociology , computer science , programming language
We recently identified several (4-8) quantitative trait loci (QTL) for 3 physical activity traits (daily distance, duration, and speed voluntarily run) in an F(2) population of mice derived from an original intercross of 2 strains that exhibited large differences in activity. These QTL cumulatively explained from 11% to 34% of the variation in these traits, but this was considerably less than their total genetic variability estimated from differences among inbred strains. We therefore decided to test whether epistatic interactions might account for additional genetic variation in these traits in this same population of mice. We conducted a full genome epistasis scan for all possible interactions of QTL between each pair of 20 chromosomes. The results of this scan revealed an abundance of epistasis, with QTL throughout the genome being involved in significant interactions. Overall, epistatic effects contributed an average of 26% of the total variation among the 3 activity traits. These results suggest that epistatic interactions of genes may play as important a role in the genetic architecture of physical activity traits as single-locus effects and need to be considered in future candidate gene identification studies.