Genome-wide linkage scan for physical activity levels in the Quebec family study

Purpose and Methods: It is commonly recognized that there is familial aggregation for physical activity level. However, the genes and sequence variants responsible for the familial clustering have not been investigated. We performed a genome-wide linkage scan based on 432 markers typed in 767 subjects from 207 families of the Quebec Family study with the aim of identifying loci affecting physical activity levels. Four physical activity level phenotypes were used. Results: Promising evidence of linkage (P < 0.0023) was found for physical inactivity on chromosome 2p22-p16. Suggestive linkages (0.0023 <P < 0.01) were found for inactivity (7p11.2, 20q13.1), total physical activity (13q22-q31), moderate to strenuous physical activity (4q28.2, 7p11.2, 9q31.1, 13q22-q31), and time spent in physical activity (11p15 and 15q13.3). Conclusion: This study identified several chromosomal regions harboring genes that may contribute to the propensity to be physically active or sedentary.