Association of Glutathione S-Transferase genes (GSTM1 and GSTT1) polymorphisms with hypertension in lead-exposed workers

It is proposed that lead concentrations in the blood are related to intracellular glutathione and lead might be conjugated with glutathione non-enzymatically or enzymatically via glutathione S-Transferase (GST). Essential hypertension is a complex, multifactorial and polygenic disease in which the underlying genetic components remain unknown. This study was aimed to investigate GST-mu1 (GSTM1) and GST-Theta1 (GSTT1) gene polymorphisms in lead-exposed workers and their relationship with blood lead levels and leadrelated hypertension. To address the possible association, GSTM1 and GSTT1 (homozygous deletion vs. non-deleted) polymorphisms in 755 lead-exposed male workers were analyzed. GSTM1 and GSTT1 polymorphisms were determined using a Multiplex PCR. We observed significant association in positive alleles of GSTT1 (OR=1.593, 95% CI=1.157-2.194). However, no significant association in GSTM1 was observed with lead-related hypertension. For combined analysis with GSTM1 and GSTT1, both positive type (+/+) and GSTT1 positive (-/+) group showed significant differences between groups. These data suggest that the GSTT1 positive type polymorphism might be associated with lead-related hypertension in the lead-exposed male workers.