The mean Hb count (g/dL) was significantly higher in subjects with HTN than in boys (14.90 ± 1.1 vs. 14.44 ± 1.0, p < 0.001) or girls (13.43 ± 0.93 vs. 13.21 ± 0.93, p < 0.001) with normal BP. The gene discussed is GSTM1; the disease is hypertensive disorder.