Polymorphisms of transcription factor-7-like 2 (TCF7L2) gene in Tunisian women with polycystic ovary syndrome (PCOS)

• A relationship between TCF7L2 variants and PCOS was suggested by some studies.
• TCF7L2 variant allele frequencies were comparable between PCOS cases and controls.
• Weak, or no contribution of TCF7L2 variants to PCOS pathogenesis among Tunisians

Background and aimsPolycystic ovary syndrome (PCOS) is a common endocrine disorder that affects women in their child-bearing age, and is often associated with insulin resistance and type 2 diabetes (T2DM). Given the overlap between PCOS and T2DM, we investigated the association of transcription factor-7-like 2 (TCF7L2) variants rs4506565, rs7903146, rs12243326, and rs12255372 with the susceptibility to PCOS.Subjects and methodsStudy subjects comprised 119 Tunisian women with PCOS (mean age 29.8 ± 4.7 years), and 150 control women (mean age 30.6 ± 5.9 years). TCF7L2 genotyping was done by the allelic discrimination/real-time PCR method.ResultsMinor allele frequencies (MAFs) of rs4506565 (P = 0.61), rs7903146 (P = 0.68), rs12243326 (P = 0.56), and rs12255372 (P = 0.60) were comparable between PCOS cases and control subjects. As the four tested TCF7L2 variants were in linkage disequilibrium, 4-locus (rs4506565, rs7903146, rs12243326, rs12255372) haplotype analysis demonstrated that haplotype 2111 was initially negatively associated with PCOS [P = 0.035; OR (95% CI) = 0.13 (0.02–0.85)], which was later lost upon correcting for multiple comparisons [Pc = 0.248].ConclusionOur data suggest that there is weak or no contribution of TCF7L2 gene polymorphism to PCOS in Tunisian women. Further studies with larger samples are necessary to confirm this observation.