ABSTRACT
AIM: The aim of this study was to analyze the association and susceptibility of Single Nucleotide Polymorphisms (SNPs) in the DRD2 and BDNF genes with BED in patients with weight regain in the postoperative period of bariatric surgery. METHODS: One hundred and seventy-seven individuals who underwent bariatric surgery with weight regain were evaluated and divided into two groups according to the BED diagnostic. The individuals were submitted to an anthropometric evaluation, analysis of the presence of BED using a validated questionnaire, and blood collection for genotyping of the polymorphisms rs6265 (BDNF) and rs1800497 (DRD2) by real-time polymerase chain reaction (RT-PCR). RESULTS: The presence of wild-type alleles for rs1800497 (CC) and rs6265 (GG) was more frequent in patients without BED. Nevertheless, the presence of one or two variant alleles for rs1800497 (CT + TT) and rs6265 (GA + AA) was more frequent in patients with BED. The combination of the two studied SNPs prevailed in patients with BED. CONCLUSIONS: The presence of allele frequency of rs1800497 SNP in the DRD2 gene and rs6265 SNP in the BDNF gene, isolated and/or combined, indicated an additional risk for the development of BED in patients with obesity, especially in the context of weight regain. LEVEL OF EVIDENCE: III (evidence obtained from the case-control analytic study).
Subject(s)
Bariatric Surgery , Binge-Eating Disorder , Binge-Eating Disorder/genetics , Brain-Derived Neurotrophic Factor/genetics , Humans , Polymorphism, Single Nucleotide , Receptors, Dopamine D2/genetics , Weight Gain/geneticsABSTRACT
BACKGROUND/AIM: We studied the molecular pathogenesis of obesity, involving complex interactions between environmental and genetic factors, with a focus on the leptin gene. It was our aim to characterize the LEP -2548G>A leptin polymorphism and lipid profile in obese and normal-weight individuals. METHODS: A total of 212 individuals were divided into the study group including 136 obese patients (body mass index, BMI≥30) and the control group with 76 normal-weight individuals (BMI>18.5 and ≤24.9). DNA was amplified by polymerase chain reaction and restriction fragment length polymorphism. The lipid profile was analyzed by enzymatic colorimetric methods. The level of significance was set at p<0.05. RESULTS: There was a prevalence of the GA genotype in both groups. However, comparative group analysis showed an association of the recessive model (AA+GA) with increased triglycerides (TG) and decreased high-density lipoprotein cholesterol (HDL-C) levels in the study group. CONCLUSION: This study did not confirm an association between obesity and the LEP -2548G>A polymorphism. However, AA+GA genotypes, in the presence of obesity, seem to contribute to a reduction in HDL-C and an increase in TG compared with normal-weight individuals. This should be confirmed in further studies.