Study-specific (first author, year of publication (reference no.)) and meta-log odds ratios (ORs) with 95% confidence intervals (CIs) for a glutathione S-transferase pi gene (GSTP1) exon 5 (Ile105Val, 313A → 313G) polymorphism for individuals carrying at least 1 valine allele (Ile/Val and Val/Val vs. Ile/Ile), by ethnicity. The shading around the point estimate reflects the weight of the study in the meta-analysis. The dashed line indicates the overall OR. ID, an assigned study identifier for each study population; Ile, isoleucine.