Background: Previous studies suggested that the single nucleotide polymorphisms of
Pro12Ala located within the PPARG gene were significantly associated with the T2DM. Recently, the
genetic studies on Pro12Ala were conducted in the different ethnic groups and the results of each study
were shown to be inconsistent. Moreover, the systematic review has not been updated since 2000.
Objective: To further validate the risk of Pro12Ala for T2DM disease based on the genetic data.
Methods: The genetic studies on the Pro12Ala in the T2DM were searched in the PubMed and PMC
database from January 2000 to October 2017. The meta-analysis was conducted with the CMA software.
Results: The meta-analysis collected 14 studies including 20702 cases and 36227 controls. The combined
analysis of all studies found that Pro12Ala was shown to be significantly associated with T2DM
and the Ala allele played the increasing risks for the disease. Nevertheless, publication bias was detected
in the combined analysis. The subgroup analysis indicated that Pro12Ala was found to be
significant in the Caucasian and Chinese population. There was no heterogeneity and publication bias in
these two groups.
Conclusion: The meta-analysis confirmed the evidence that the Pro12Ala was the susceptible variant
for the decreasing risks for the T2DM.