Additive Effects of the Mutations in theβ3-Adrenergic Receptor and Uncoupling Protein-1 Genes on Weight Loss and Weight Maintenance in Finnish Women1

This study examined whether the Trp64Arg mutation in theβ 3-adrenergic receptor (β3AR) and the A→G mutation in the uncoupling protein-1 (UCP-1) genes have associations with weight loss and subsequent weight maintenance. Seventy-seven obese (body mass index range, 29–46 kg/m2), clinically healthy, premenopausal women were studied. A 12-wk weight reduction by very low calorie diet (VLCD) was followed by a 40-wk weight maintenance phase. The subjects were divided into four groups according to theirβ 3AR and UCP-1 genotype: no mutation (control; n = 37), only Trp64Arg mutation in the β3AR gene (n = 12), only A→G mutation in the UCP-1 gene (n = 23), and both mutations (n = 5). Subjects with both mutations had a lower weight reduction during VLCD than the controls [−10.5 ± 0.6 (±sem) vs. −14.0 ± 0.5 kg; P = 0.051, by ANOVA]. During the maintenance phase, weight in subjects with both mutations increased by 5.8 ± 1.5 kg, but remained unchanged in the controls (−0.5 ± 0.8 kg; P = 0.041). The changes in weight in s...