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

• Published in: Surgery for obesity and related diseases Vol. 17; no. 7; pp. 1263 - 1270
• Main Authors: de Oliveira, Mayara S., Rodrigues, Michelle, Rossoni, Elis A., Sortica, Denise A., Rheinheimer, Jakeline, Moehlecke, Milene, Heredia, Mariana L.D. C., Horvath, Jaqueline D.C., Kops, Natalia L., Trindade, Manoel R.M., Viana, Luciana V., Leitão, Cristiane B., Friedman, Rogério, Crispim, Daisy, de Souza, Bianca M.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01-07-2021
• Subjects: Bariatric surgery; Body Mass Index; Gastric Bypass; Humans; Ion Channels - genetics; Longitudinal Studies; Mitochondrial Proteins - genetics; Obesity; Obesity, Morbid - genetics; Obesity, Morbid - surgery; Polymorphisms; Retrospective Studies; UCP2; Uncoupling Protein 2 - genetics; Weight loss; Weight Loss - genetics; Obesity; Polymorphisms; Bariatric surgery; UCP2; Weight loss
• ISSN: 1550-7289; 1878-7533
• DOI: 10.1016/j.soard.2021.03.032

Uncoupling protein 2 (UCP2) plays an important role in energy expenditure regulation. Previous studies have associated the common −866G/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.
To investigate whether UCP2 −866G/A and Ins/Del polymorphisms are associated with weight loss outcomes after bariatric surgery.
Longitudinal study in a university hospital.
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.
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 (Δ) 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.
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 ΔBMI 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.
•Carriers of -866A/A genotype maintained higher BMI at 6, 12 and 18 months after RYGB compared to G/G patients.•In -866A/A carriers, excess weight was higher while EWL% was lower at 6 and 12 months after RYGB compared to G/G carriers.•Ins allele of Ins/Del polymorphism seems to be associated with lower BMI change 12 months after RYGB surgery.