Incidence of clinical malaria from 6 to 18 months was independently associated with Hb concentration and HFIAS at 6 months (i.e. each g/L higher Hb at 6 months was associated with 1% decrease in incidence of clinical malaria; and 1-unit higher HFIAS was associated with 2% increase in incidence of clinical malaria). The gene discussed is GSTM1; the disease is malaria.