Lack of association between genetic polymorphisms within KCNQ1 locus and type 2 diabetes in Tunisian Arabs

Diabetes Res Clin Pract. 2012 Dec;98(3):452-8. doi: 10.1016/j.diabres.2012.10.006. Epub 2012 Oct 27.

Abstract

Aims: Polymorphisms of KCNQ1 were previously associated with type 2 diabetes (T2DM) in select Caucasian and non-Caucasian populations. We investigated the association of rs231361, rs231359, rs151290, rs2237892, rs2283228, rs2237895, and rs2237896 KCNQ1 polymorphisms with T2DM in Tunisian Arabs.

Subjects and methods: Subjects comprised 900 T2DM patients and 600 normoglycemic controls. KCNQ1 genotyping was done by allelic discrimination (real-time PCR) and PCR-RFLP methods; the contribution of KCNQ1 polymorphisms to T2DM were analyzed by Haploview and regression analysis.

Results: Minor allele frequency (MAF) of the 7 tested KCNQ1 variants was comparable between T2DM cases and controls. Mild association of rs2237892 genotypes with T2DM was seen (P=0.014), highlighted by the significant association of the C/T genotype with increased T2DM risk (OR, 2.11; 95%CI, 1.25-3.53), after adjusting for BMI, gender, systolic and diastolic blood pressure, and serum lipid profile. Heterogeneity in linkage disequilibrium pattern between tested KCNQ1 variants analyzed was seen. Two-locus (rs231361 and rs231359) and 5-locus (remaining 5 SNPs) haplotype analysis did not reveal any significant association with any of the haplotypes contained in either block 1 or block 2.

Conclusion: These results indicate that there was no evidence for an association of KCNQ1 polymorphisms with T2DM in Tunisian Arabs.

Publication types

  • Multicenter Study

MeSH terms

  • Aged
  • Alleles
  • Arabs
  • Case-Control Studies
  • Diabetes Mellitus, Type 2 / genetics*
  • Diabetes Mellitus, Type 2 / metabolism
  • Female
  • Gene Frequency
  • Genetic Association Studies
  • Haplotypes
  • Humans
  • KCNQ1 Potassium Channel / genetics*
  • KCNQ1 Potassium Channel / metabolism
  • Linkage Disequilibrium
  • Male
  • Middle Aged
  • Outpatient Clinics, Hospital
  • Polymorphism, Single Nucleotide*
  • Tunisia

Substances

  • KCNQ1 Potassium Channel
  • KCNQ1 protein, human