Uncoupling protein-2/uncoupling protein-3 gene polymorphism is not associated with anorexia nervosa.

Energy expenditure abnormalities have been observed in anorexia nervosa (AN). The uncoupling proteins (UCPs) have been implicated as having a role in energy metabolism and thermogenesis, and an association between a marker flanking the UCP-2/UCP-3 gene cluster and AN has been reported. Also known are insertion/deletion and −866G/A polymorphisms in the UCP-2 gene, and the −55C/T polymorphism in the UCP-3 gene. Differences in these alleles are reportedly related to changes in energy expenditure, body mass index, fat tissue accumulation and obesity. Therefore, this case–control association analysis was done to determine whether any of these UCP-2/3 gene polymorphisms are related to a predisposition to AN. In analysis of a cohort of 106 female Japanese AN sufferers and 126 normal female controls, we found no between-group differences in the polymorphism frequencies of these groups. The hypothesis that differences in the UCP-2/3 gene influence the susceptibility to AN was not supported.