A meta-analysis on the association between PPAR-γ Pro12Ala polymorphism and polycystic ovary syndrome

Purpose To investigate the influence of the peroxisome proliferator activated receptor gamma (PPAR-γ) Pro12Ala polymorphism on the susceptibility of polycystic ovary syndrome (PCOS) and body mass index (BMI), fast insulin levels, homeostasis model assessment of insulin resistance (HOMA-IR) in PCOS patients. Methods PubMed, EMBASE, MEDLINE and CENTRAL databases were searched to identify eligible studies. We then conducted a meta-analysis to examine the association between Pro12Ala polymorphism and PCOS. Results Seventeen eligible studies, including 2,149 patients and 2,124 controls were enrolled in this meta-analysis. Pro12Ala polymorphism was significantly associated with the susceptibility of PCOS (odds ratio [OR] 0.74, 95 % confidence interval [CI] [0.61, 0.90] for allele; OR 0.70, 95 % CI [0.57, 0.86] for genotype). In the European subgroup of PCOS, the X/Ala genotype was associated with lower BMI (mean difference [MD] −1.08, 95 % CI [−2.08, −0.09]) and fast insulin levels (MD −19.82, 95 % CI [−34.07, −5.58]). However, this polymorphism did not display an impact on HOMA-IR in PCOS patients. Conclusions Ala variant would decrease the risk of PCOS and result in lower BMI and fast insulin levels in a European population, but had no impact on HOMA-IR in PCOS patients. Further studies are required to elucidate these associations more clear.