Polymorphism in genes encoding xenobiotic-metabolizing enzymes (GSTM1 and GSTT1) and the risk of asthma onset in Moldovan and other ethnic groups: a meta-analysis

Abstract

Background. The aim of the study was to examine the association of the risk of asthma onset with polymorphisms in genes encoding proteins xenobiotic metabolizing enzymes (GSTT1 and GSTM1) in Moldovans and other ethnic groups using the meta-analysis method. Methods. A meta-analysis of the association of genetic polymorphism of GSTT1 and GSTM1 genes and the risk of asthma development in 180 Moldovan subjects in comparison with published data on various ethnogeographical affiliations was performed. Results. The meta-analysis results were based on sixteen studies which included a total number of 3873 patients and 4863 healthy individuals. The meta-analysis showed an increased risk of disease development in subjects who are carriers of the GSTM1 null genotype (odds ratio of the cumulative risk was 1,29; 95% CI 1,09-1,54), whereas the GSTT1 0/0 genotype was associated with a 1,32 fold increase of the cumulative risk of asthma onset (95% CI 0,99-1,75). Conclusion. The obtained results suggest that the risk of asthma development is associated with the deletion polymorphism in genes encoding proteins xenobiotic metabolizing enzymes (GSTT1 and GSTM1), but the mechanisms of the disease also depend on the gene-by-gene and gene-environment interactions.