Additionally, female smokers were shown to have a higher risk of bladder cancer when their blood samples had the GSTM1 deletion genotype, but not in non-smokers (Karagas et al., 2005), possibly due to females with the GSTM1 null genotype being unable to metabolize carcinogens in cigarette smoke. The gene discussed is GSTM1; the disease is urinary bladder cancer.