RESUMO
Gluthathione-S-transferase (GSTM1 and GSTP1) and nicotinamide quinone oxidoreductase (NQO1) genes play an important role in cellular protection against oxidative stress; which has been linked to asthma pathogenesis. We investigated whether common; functional polymorphisms in GSTM1; GSTP1; and NQO1 influence susceptibility to asthma among schoolchildren in South Africa. Genomic deoxyribonucleic acid (DNA) was extracted from 317 primary schoolchildren; aged 9-11 years; from the urban; underprivileged socio-economic communities of Durban. GSTM1 (null vs. present genotype); GSTP1 (Ile105Val; AA ?AG+GG) and the NQO1 (Pro/Ser; CC ?CT/TT) genotypes were determined using polymerase chain reaction. Among the children; 30 were GSTM1 null; 65 carried the G allele for GSTP1; and 36 carried the C allele for NQO1.There was a high prevalence of asthma of any severity (46.1); with 20.4 reporting persistent asthma. The GSTP1 AG+GG polymorphic genotype was significantly associated with persistent asthma (adjusted OR = 3.98; CI = 1.39; 11.36; p-value = 0.01). Neither the GSTM1; nor the NQO1; genotype was a significant predictor of persistent asthma. Therefore; the GSTP1 A/G variant may modulate the risk of persistent asthma among our sample