Can study of the ADRB3 gene help improve weight loss programs in obese individuals?

Obesity is a chronic disease of multifactorial origin characterized by excess weight and excess fat accumulation, and whose etiology includes intrinsic (genetic, physiological, and metabolic) and extrinsic (social and cultural) factors. Fat accumulation is caused by a prolonged imbalance in the energy balance influenced, among other factors, by adaptive thermogenesis, which is triggered by cold environmental conditions, or by hypercaloric intake. Thermogenesis is regulated by the sympathetic nervous system and occurs in the muscle and brown adipose tissue. There are adrenergic receptors in brown adipose tissue, including the beta-3 adrenergic receptor (ADRB3), the main receptor for the regulation of thermogenesis. The presence in heterozygosis of an SNP-type polymorphism in the ADRB3 gene (Trp64Arg; rs4994) is associated with a lower lipolytic activity, a predisposition to obesity, and resistance to weight loss. The objective of this study was to analyze through a systematic review the weight loss program most appropriate for carriers.

A retrospective study of published papers on rs4994 polymorphism in the SNP and PubMed databases was conducted.

Most published studies suggest the presence of obesity and resistance to weight loss in carriers, and report significant improvements in anthropometric parameters when patients receive fat-rich hypocaloric diets.

Based on these conclusions, specific nutritional and physical exercise guidelines are proposed for individuals carrying the Trp64Arg allele.