Estrogen receptor-alpha gene polymorphisms and body composition in children and adolescents.

Background/aims: Gender differences in body composition are largely explained by differences in sex hormones, such as estrogens. Associations between 2 polymorphisms in the estrogen receptor-α gene (ESR1) and body composition in children and adolescents were investigated.

Methods: Two comparable Dutch cohorts with a generational difference of about 20 years were investigated. The first consisted of 350 subjects (184 girls) and the second of 316 subjects (155 girls). Associations between height, weight, BMI, fat mass (FM) and fat-free mass and two polymorphisms in the ESR1 gene were investigated.

Results: In girls in the recent cohort, the PvuII-XbaI haplotype 2 polymorphism in the ESR1 gene was associated with a lower body weight, BMI, and FM. These associations were not observed in the older cohort. The younger cohort had a significantly higher total FM, body weight and BMI compared to the older cohort.

Conclusion: Because the associations between the PvuII-XbaI haplotype 2 polymorphism and body FM in girls were only found in the recent cohort, but not in a comparable, generally leaner cohort from an older generation, it is suggested that non-carriers of this polymorphism are likely to be more vulnerable to fat accumulation in today's obesity promoting environment, than carriers.