Vol 4, No 2 (2003): Practical Diabetology
Research paper
Published online: 2003-04-28
Vitamin D receptor gene polymorphisms and the risk of coronary artery disease in a Polish population with type 2 diabetes mellitus and with normal glucose metabolism
Diabetologia Praktyczna 2003;4(2):137-144.
Abstract
INTRODUCTION. Vitamin D plays an important role
in calcium and phosphates metabolism. There is evidence
that this steroid modifies the risk factors of
coronary artery disease (CAD). Thus genes that are
involved in vitamin D metabolism are good candidates
for CAD in genetic studies. One of those genes
vitamin D receptor (VDR). For example, an association
between one of many VDR polymorphisms
(BsmI) and CAD was shown in a German population,
particularly among patients with type 2 diabetes
mellitus (T2DM).
AIM. To search for the association of FokI, ApaI, BsmI, and TaqI polymorphisms of the VDR gene with CAD in two Polish cohorts of unrelated individuals: with and without T2DM.
MATERIAL AND METHODS. Overall, we included 521 individuals into this analysis: 292 patients with T2DM and 229 without T2DM. The diagnosis of CAD in both groups was based on a questionnaire and patient medical records. All individuals included into the analysis were previously genotyped for frequent VDR polymorphisms: FokI, ApaI, BsmI, and TaqI. Alleles were defined based on restriction fragment length polymorphism method (RFLP). Since variants of ApaI, BsmI, and TaqI polymorpshisms were in very strong linkage disequilibrium, three loci haplotypes could be assigned to phase-unknown individuals with high degree of confidence. Differences in distribution were assessed by c2 test.
RESULTS. In the group of T2DM patients, the diagnosis of CAD was established in 35.93% individuals, while in the group without T2DM this number was 26.32%. There was no difference between the carriers of the different genotypes of the four examined markers with respect to the frequency of CAD diagnosis of each group both separately or when analyzed jointly. We observed, however, that the carriers of bAT/baT three point haplotype combinations were diagnosed with CAD less frequently than the carriers of all other haplotype combination: 25.58% vs. 37.75%; p = 0.125 in T2DM group, 14.29% vs. 27.86% in the group without T2DM; p = 0.126 and 21.13% vs. 33.33%; p = 0.03 in the joint analysis of both groups, respectively.
CONCLUSION. The results of our study suggest that polymorphisms of the VDR gene may influence the risk of CAD in a Polish population.
AIM. To search for the association of FokI, ApaI, BsmI, and TaqI polymorphisms of the VDR gene with CAD in two Polish cohorts of unrelated individuals: with and without T2DM.
MATERIAL AND METHODS. Overall, we included 521 individuals into this analysis: 292 patients with T2DM and 229 without T2DM. The diagnosis of CAD in both groups was based on a questionnaire and patient medical records. All individuals included into the analysis were previously genotyped for frequent VDR polymorphisms: FokI, ApaI, BsmI, and TaqI. Alleles were defined based on restriction fragment length polymorphism method (RFLP). Since variants of ApaI, BsmI, and TaqI polymorpshisms were in very strong linkage disequilibrium, three loci haplotypes could be assigned to phase-unknown individuals with high degree of confidence. Differences in distribution were assessed by c2 test.
RESULTS. In the group of T2DM patients, the diagnosis of CAD was established in 35.93% individuals, while in the group without T2DM this number was 26.32%. There was no difference between the carriers of the different genotypes of the four examined markers with respect to the frequency of CAD diagnosis of each group both separately or when analyzed jointly. We observed, however, that the carriers of bAT/baT three point haplotype combinations were diagnosed with CAD less frequently than the carriers of all other haplotype combination: 25.58% vs. 37.75%; p = 0.125 in T2DM group, 14.29% vs. 27.86% in the group without T2DM; p = 0.126 and 21.13% vs. 33.33%; p = 0.03 in the joint analysis of both groups, respectively.
CONCLUSION. The results of our study suggest that polymorphisms of the VDR gene may influence the risk of CAD in a Polish population.
Keywords: vitamin D receptorgenecoronary artery diseasetype 2 diabetes mellitus