Associations of markers in 11 obesity candidate genes with maximal weight loss and weight regain in the SOS bariatric surgery cases

Purpose: To test whether DNA sequence variation in 11 obesity genes is associated with maximum weight loss and weight regain over 6 years of follow-up in bariatric surgery patients of the Swedish obese subjects (SOS) intervention study. Methods: A total of 1443 subjects were available for analysis (vertical banded gastroplasty: n=966, banding: n=293 and gastric bypass: n=184). Single-nucleotide polymorphisms (SNPs) from the following 11 genes were included: ADIPOQ, BDNF, FTO, GNB3, LEP, LEPR, MC4R, NR3C1, PPARG, PPARGC1A and TNF. General linear models were used to analyze associations between the SNPs and maximum weight loss and weight regain. Results: The average maximum weight loss was 33.7 kg (s.d. 13.3; min -95.5 kg, max +2.0 kg), which was reached 2.2 (s.d. 1.6) years after the surgery. Subjects regained approximately 12 kg (range 0.0-51.4 kg) by year 6. After correcting for multiple testing, the FTO SNP rs16945088 remained significantly associated with maximum weight loss (P=0.0002), as minor allele carriers lost approximately 3 kg less compared with common allele homozygotes. This association was particularly evident in the banding surgery patients (P