effect of CYP19 and COMT polymorphisms on exercise-induced fat loss in postmenopausal women

Objective:To examine whether genetic polymorphisms in CYP19 [intron 4 (TTTA)n; n = 7 to 13 and a 3‐base pair deletion, which is in strong linkage disequilibrium with the seven repeat] and COMT (Val108/158Met) modified the change in BMI, total and percentage body fat, or subcutaneous and intra‐abdominal fat during a year‐long exercise intervention trial. These genes metabolize estrogens and androgens, which are important in body fat regulation. Research Methods and Procedures: A randomized intervention trial was used, with an intervention goal of 225 min/wk of moderate‐intensity exercise for one year. Participants (n = 173) were postmenopausal, 50 to 75 years old, sedentary, overweight or obese, and not taking hormone therapy at baseline. Results: Exercisers with two vs. no CYP19 11‐repeat alleles had a larger decrease in total fat (−3.1 kg vs. −0.5 kg, respectively, p = 0.01) and percentage body fat (−2.4% vs. −0.6%, respectively, p = 0.001). Exercisers with the COMT Met/Met vs. Val/Val genotype had a smaller decrease in percentage fat (−0.7% vs. −1.9%, respectively, p = 0.05). Among exercisers, women with the COMT Val/Val genotype and at least one copy of the CYP19 11‐repeat allele vs. those with neither genotype/allele had a significantly larger decrease in BMI (−1.0 vs. +0.1 kg/m2, respectively, p = 0.009), total fat (−2.9 vs. −0.5 kg, respectively, p = 0.004), and percentage body fat (−2.6% vs. −0.4%, respectively, p < 0.001). Discussion: Genetic polymorphisms in CYP19 and COMT may be important for body fat regulation and possibly modify the effect of exercise on fat loss in postmenopausal women.