Relationship of the CDKAL1 and KCNQ1 gene polymorphisms to the age at diagnosis of type 2 diabetes in the Slovakian population

Czech version

Authors: M. Dobríková ¹; M. Javorský ¹; V. Habálová ²; L. Klimčáková ²; M. Kozárová ¹; J. Židzik ²; J. Halušková ²; J. Šalagovič ²; I. Tkáč ¹
Authors‘ workplace: IV. interná klinika Lekárskej fakulty UPJŠ a Centra excelentnosti pre výskum aterosklerózy a jej komplikácií – srdcového a mozgového infarktu (CEVA) Lekárskej fakulty UPJŠ Košice, Slovenská republika, prednosta prof. MUDr. Ivan Tkáč, PhD. ¹; Ústav lekárskej biológie Lekárskej fakulty UPJŠ a Centra excelentnosti pre výskum aterosklerózy a jej komplikácií – srdcového a mozgového infarktu (CEVA) Lekárskej fakulty UPJŠ v Košice, Slovenská republika, prednosta prof. RNDr. Ján Šalagovič, PhD. ²
Published in: Vnitř Lék 2011; 57(2): 155-158
Category: Original Contributions

Overview

Background/aims:

The association of CDKAL1 and KCNQ1 genes with type 2 diabetes mellitus (DM2T) was confirmed by several genome-wide association studies in both Caucasian and Asian populations. For both genes, it is supposed that the risk of DM2T development is related to impaired insulin secretion. Based on assumption that the presence of risk allele might predispose to an earlier onset of DM2T, the aim of the present study was to assess the frequency of risk alleles of CDKAL1 rs7756992 and KCNQ1 rs163184 polymorphisms and to analyze their association with the age at DM2T diagnosis in the Slovakian population.

Methods:
CDKAL1 rs7756992 A/G and KCNQ1 rs163184 G/T polymorphisms were genotyped using asymmetric PCR with subsequent melting curve analysis in a group of 538 patients with DM2T. Anthropometric and laboratory parameters were determined by using standard methods. Since two genes were analysed, the required level for statistical significance was defined as p < 0.025.

Results:
Risk homozygotes (GG) for KCNQ1 polymorphism had higher mean age of DM2T diagnosis by 2 years when compared to T-allele carriers (GT + TT) in a recessive model, but the difference did not reach the predefined level of statistical significance. No relationship of CDKAL1 polymorphism to the age at onset of DM2T diagnosis was observed.

Conclusions:
In the present study, no relationship of CDKAL1 and KCNQ1 polymorphisms to the earlier onset of type 2 diabetes was observed.

Key words:
type 2 diabetes mellitus – gene polymorphisms – CDKAL1 – KCNQ1 – age at diagnosis of diabetes

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