Thesis & Dissertations

Adiponectin (ADIPOQ) is an adipocyte-produced protein that is widely recognized as a key determinant of insulin sensitivity. Recent genome-wide scans (GWAS) have mapped diabetes susceptibility loci on chromosome 3q27, where adiponectin gene is located. Several association studies of type 2 diabetes and ADIPOQ gene polymorphisms have been reported and yielded in conflicting results. This study aimed to examine the association of the promoter variant rs266729 (-11377 C/G) and exon 2 variant rs2241766 (+45 T/G) of ADIPOQ gene as a risk factor for type 2 diabetes in Lebanon. Genotyping of the two SNPs of adiponectin gene was performed in 50 type 2 diabetic patients and 50 control subjects. Genomic DNA was isolated from venous blood samples, quantified and subjected to polymerase chain reaction and restriction fragment length polymorphism using specific primers and restriction endonucleases for each polymorphism. SPSS program was used for statistical analysis. Studying the different genotypic frequency distributions of ADIPOQ -11377 C/G and +45 T/G SNPs between diabetic patients and control subjects revealed statistical results that did not reach a significant level. Allelic frequency distributions of -11377 C/G SNP for T2DM were 75 % for C allele and 25% for G allele; While controls were 77% for C allele and 23% for G allele (p=0.74). The allele frequency for +45 T/G SNP in T2DM was 91 % for T allele and 9% for G allele; While controls were 94% for T allele and 6% for G allele; p=0.42. The allele frequency in both SNPs did not differ significantly. There was a significant association between GG genotype of -11377 C/G SNP and increased creatinine levels in diabetic patients (p=0.003). There was also significant association between TG genotype of +45 T/G SNP and increased SGPT levels in the control subjects (p=0.019). This study showed that there was no association between ADIPOQ -11377 C/G and +45 T/G gene polymorphisms with type 2 diabetes in the Lebanese population. However, GG genotype of -11377 C/G SNP and TG genotype of +45 T/G SNP altered the kidney function in the diabetic patients and liver function in the control subjects, respectively.