A genetic variant in <i><scp>IL</scp>‐15R</i>α correlates with physical activity among European–American adults

Abstract

BACKGROUND: Interleukin-15 (IL-15) is a myokine associated with muscle strength, possibly by attenuating protein breakdown. A variant in the alpha-receptor (IL-15Rα 1775 A>C, rs2228059) partially modulates the muscle strength and size response to resistance training. We examined if this polymorphism associated with habitual physical activity among European-American adults. METHODS: ) were genotyped. Physical activity phenotypes were derived from the Paffenbarger Physical Activity Questionnaire. Analysis of covariance (ancova) tested log-transformed differences between the IL-15Rα genotype and physical activity phenotypes by gender with age and BMI as covariates. RESULTS: Men with the IL-15Rα 1775AA genotype spent more time in light intensity physical activity (39.4 ± 2.4 hr/week) than men with the CC genotype (28.6 ± 2.3 hr/week, (p = .009). CONCLUSION: Further research is needed to confirm our finding and determine the possible mechanisms by which the IL-15Rα variant modulates light intensity physical activity.