Genetic association of the BsmI variant of vitamin D receptor gene with risk of morbid obesity.

Objective: The aim of this study was to evaluate the vitamin D receptor (VDR) BsmI variant in morbidly obese patients compared with healthy normal controls.

Methods: The study included 103 patients with morbid obesity and 120 healthy individuals serving as normal controls. The DNA samples obtained from blood were genotyped using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique. The gender, age, smoking status, triglycerides, total cholesterol, insulin, mean body mass index, and frequency of allele and genotype of the BsmI variant in the VDR gene in morbidly obese patients were evaluated.

Results: The body mass index of the patients was 47.14 ± 7.19. The VDR B/B, B/b, and b/b genotype frequencies were 27.2% versus 28.3%; 54.4% versus 50%; and 18.4% versus 21.7% in the morbidly obese patients and the control group, respectively. There was no statistically significant difference between patients and control subjects in the genotype and allele distribution of the VDR BsmI variant (p>0.05). Both patients and control genotype frequencies are consistent with Hardy-Weinberg equilibrium.

Conclusion: The BsmI variant in the VDR gene may not seem to predispose to morbid obesity in our study population. Further studies with a larger number of subjects are needed to make a more precise evaluation of this relationship.