The female group had a higher BMI (27.6 vs. 26.7; P = 0.02), and also a higher proportion of anaemia, here defined as Hb < 120 g/L (35 vs. 16; P = 0.003), and a higher mean HDL (1.6 mmol/L vs. 1.3 mmol/L; P < 0.0001). The gene discussed is GSTM1; the disease is anemia (phenotype).