Background: The prevalence of dyslipidemia is rising alarmingly in elderly Han Chinese male patients with type 2 diabetes mellitus (T2DM). The genetic factors that contribute to the development of diabetic dyslipidemia remain incompletely identified. This study was conducted to assess the association between vitamin D receptor (VDR) polymorphisms and development of dyslipidemia in the Han elderly male population with T2DM in North China.
Methods: A total of 242 T2DM patients with dyslipidemia (DH group, n=108) or without dyslipidemia (DO group, n=134) and 100 controls were genotyped for ApaI, TaqI and FokI single nucleotide polymorphisms (SNPs) of the VDR gene using polymerase chain reaction-restriction fragment length polymorphism and sequencing. The frequency and distribution of the SNPs were compared between cases and controls.
Results: The distribution of genotypes of VDR-FokI was significantly different between the control and DM group (P=0.033), as well as between the control and DH subgroup (P=0.011) but not DO subgroup (P=0.111). The frequency of C allele and CC genotype of FokI was significantly higher in the DH patients than in the controls (P=0.015 and P=0.003, respectively). Logistic regression analysis in a dominant model homozygous for the C allele of the FokI SNP showed that CC genotype was associated with DH patients (OR =1.797, 95% CI: 1.077-2.999, P=0.025). Significant associations of the ApaI and TaqI SNPs with either DO or DH subjects were not observed.
Conclusion: These findings suggest that CC genotype of VDR-FokI is a risk factor for T2DM patients with dyslipidemia in elderly males in North China.
Keywords: VDR; diabetes; dyslipidemia; elderly; polymorphism; vitamin D receptor.