Significant study of population stratification, sensitivity analysis and trim and fill analyses on GBA mutation and Parkinson's disease.

This comprehensive meta-analysis was applied to case-control studies of the association between PD and GBA to assess the joint evidence for the association, the influence of individual studies, and evidence for publication bias. We searched PubMed, Medline, Cochrane Library, reference lists of relevant studies to June 2012, and email contact with authors. For the case-control studies, the authors found 1) support for the association between PD and GBA, both in total group analysis [fixed: OR and 95%CI: 4.825 (3.901-5.968), P < 0.001; random: OR and 95%CI: 4.791 (3.520-6.520), P < 0.001] and in Asia, Europe, Americas, and Israel subgroups analysis [Asia: fixed: OR and 95%CI: 7.495 (4.490-12.511), P < 0.001, random: OR and 95%CI: 7.989 (4.060-15.723), P < 0.001; Americas: fixed: OR and 95%CI: 4.036 (2.460-6.622), P < 0.001, random: OR and 95%CI: 4.065 (2.464-6.707), P < 0.001; Europe: fixed: OR and 95%CI: 3.353 (2.287-4.917), P < 0.001, random: OR and 95%CI: 3.559 (2.148-5.894), P < 0.001; Israel: fixed/random: OR and 95%CI: 6.430 (4.430-9.333), P < 0.001], 2) no evidence that this association was accounted for by any one study, and 3) no evidence for publication bias. In conclusion, GBA mutation status may be significantly associated with PD.