Association between PPAR-γ2 Pro12Ala polymorphism and obesity: a meta-analysis.

Area of Science:

• Genetics
• Metabolic Disorders
• Human Physiology

Background:

• The peroxisome proliferator-activated receptor-γ2 (PPAR-γ2) gene is implicated in obesity pathogenesis.
• Previous studies on the association between PPAR-γ2 Pro12Ala polymorphism and obesity have yielded inconsistent results.

Purpose of the Study:

• To conduct a comprehensive meta-analysis to accurately assess the association between the PPAR-γ2 Pro12Ala polymorphism and obesity risk.
• To provide a clearer understanding of the genetic contribution of PPAR-γ2 to obesity susceptibility.

Main Methods:

• A systematic literature search was performed across PubMed, Wan Fang, Chinese Biomedical Medical, and Chinese National Knowledge Infrastructure databases.
• Meta-analysis included 25 studies comprising 6491 cases and 8242 controls, utilizing random-effects or fixed-effects models based on heterogeneity.
• Statistical analysis was performed using STATA 12.0 to calculate summary odds ratios (OR) with 95% confidence intervals (CI).

Main Results:

• The meta-analysis revealed a significant association between the PPAR-γ Pro12Ala polymorphism and increased obesity risk across various genetic models (e.g., Ala vs. Pro: OR = 1.55, 95% CI 1.34-1.80).
• Subgroup analyses demonstrated significant associations in Caucasians, Asians, and Mixed populations.
• Associations were observed for obesity defined by BMI cutoffs of ≥24 and ≥30, but not for BMI ≥95th percentile.

Conclusions:

• The PPAR-γ Pro12Ala polymorphism is significantly associated with an elevated risk of obesity.
• This genetic variant may contribute to obesity susceptibility across different ethnic groups.
• The findings highlight the importance of considering specific genetic factors in understanding obesity prevalence.