-866G/A and Ins/Del polymorphisms in UCP2 gene are associated with reduced short-term weight loss in patients who underwent Roux-en-Y gastric bypass

Background: Uncoupling protein 2 (UCP2) plays an important role in energy expenditure regulation. Previous studies have associated the common -8 66G/A (rs659366) and Ins/Del polymorphisms in the UCP2 gene with metabolic and obesity-related phenotypes. However, it is still unclear whether these polymorphisms influence weight loss after bariatric surgery. Objectives: To investigate whether UCP2 -866G/A and Ins/Del polymorphisms are associated with weight loss outcomes after bariatric surgery. Setting: Longitudinal study in a university hospital. Methods: We retrospectively evaluated 186 patients who underwent Roux-en-Y gastric bypass (RYGB) surgery for clinical and laboratory characteristics in the preoperative period, 6, 12, and 18 months after RYGB. The-866G/A (rs659366) polymorphism was genotyped using real-time PCR, while the Ins/Del polymorphism was genotyped by direct separation of PCR products in 2.5% agarose gels. Results: Patients with the-866A/A genotype showed higher body mass index (BMI) after 6, 12, and 18 months of surgery and excess body weight after 6 and 12 months compared with G/G patients. They also showed lower excess weight loss (EWL%) after 6 and 12 months of surgery. Ins allele carriers (Ins/Ins + Ins/Del) had lower delta (D) BMI 12 months after surgery compared with Del/Del patients. Accordingly, patients carrying haplotypes with >2 risk alleles of these polymorphisms had higher BMI and excess weight and lower EWL% during follow-up. Conclusion: UCP2-866A/A genotype is associated with higher BMI and excess weight and lower EWL% during an 18-month follow-up of patients who underwent RYGB, while the Ins allele seems to be associated with lower DBMI 12 months after surgery. Further studies are needed to confirm the associations of the-866G/A and Ins/Del polymorphisms with weight loss after bariatric surgery. (C) 2021 American Society for Bariatric Surgery. Published by Elsevier Inc. All rights reserved.

Automated summary

This study investigated the association of UCP2 -866G/A and Ins/Del polymorphisms with weight loss outcomes after bariatric surgery. Findings suggest that the -866A/A genotype is associated with higher BMI, excess weight, and lower EWL% during an 18-month follow-up, while the Ins allele may be linked to lower DBMI 12 months after surgery. Further research is needed to confirm these associations.