GSTM1 and malaria: This agrees with a previous observation that antibody response to another malaria antigen, Pf155/ring-infected erythrocyte surface antigen (RESA), increases more rapidly in HbAA than in HbAS [17] as well as another study showing that the protective effect of Hb status disappears after 6 years of age, when it is obscured by general premunition [16].