Participants with HIV/HCV co-infection with the GSTM1 genotype coding for the functional antioxidant enzyme (Table 4) had significantly lower HIV viral load (β=−0.918, p=0.022), lower mitochondrial 8-oxo-dG (β=−0.48, p=0.028), and lower rate of apoptosis (β=−67.40, p=0.009), but they also had higher oxidized glutathione (β=10.02, p=0.028) compared to those who had the null GSTM1 gene. Here, GSTM1 is linked to coinfection.