SLC6A4 gene L/S polymorphism and susceptibility to pulmonary arterial hypertension: a meta-analysis

OBJECTIVE: To investigate the association between the solute carrier family 6 member 4 (SLC6A4) gene L/S polymorphism and pulmonary arterial hypertension (PAH). METHODS: The relevant literature was retrieved from the PubMed® database and the data were extracted. STATA® version 12.0 software was used to calculate pooled odds ratios (ORs) and 95% confidence intervals (CI). RESULTS: Eight case–control studies qualified for inclusion in the meta-analysis. These studies included 1215 cases and 936 control subjects. There was no significant association between the SLC6A4 gene L/S polymorphism and PAH risk in the total population (LL versus SS: OR 1.83, 95% CI 0.95, 3.51; LS versus SS: OR 1.37, 95% CI 0.93, 2.02; dominant model: OR 1.38, 95% CI 0.97, 1.97; recessive model: OR 1.54, 95% CI 0.84, 2.83). Subgroup analysis based on study quality scores and Hardy–Weinberg equilibrium also showed no significant association. CONCLUSION: The findings of this meta-analysis suggest that the SLC6A4 gene L/S polymorphism is unlikely to be related to PAH risk. Well-designed studies with more participants will be required to validate these results.