Association of VDR gene ApaI polymorphism with obesity in Iranian population

Identifying obesity risk factors as a health problem facing communities is crucial given its complexity. The vitamin D receptor gene has been reported as a possible cause of this disease.

To study the association of the VDR gene ApaI, BsmI, and TaqI polymorphisms with obesity in an Iranian population.

We analyzed the genotypes of 348 obese (BMI≥30 kg/m2) and 320 non-obese people (BMI: 18.5-24.9 kg/m2) using PCR-RFLP. We measured FBS, TG, total cholesterol, and HDL and LDL cholesterol levels in an automatic biochemical analyzer.

We found significantly higher BMI, FBS, and TG levels in the obese group compared to the control. In the obese individuals, the frequency of genotype AA was 47.1% and that of the combined Aa+aa genotype, 52.9% while in the control group they were 30% and 70%, respectively (p=0.024, 95% confidence interval (CI)=1.100-3.933, odds ratio (OR)=2.08). A and a alleles frequencies for the ApaI polymorphism were statistically significant in the two groups (allele A vs. a; p=0.017). No significant relationship was observed between TaqI genotypes and alleles in the control and obese subjects.

We found that VDR ApaI (rs7975232 C/A) polymorphism appeared to be a risk factor for obesity. Especially, the A allele and the AA genotype in ApaI were associated with the obesity phenotypes.