G6PD and malaria: In contrast, a study of randomly sampled individuals without malaria from the Marma and Khyang ethnic groups (n = 202, approximately 60% female) also living in the Chittagong Hill Tracts (CHT) showed that 59% had normal G6PD activity, 35% had mild deficiency and 6.5% had severe deficiency [35], with apparently higher levels of deficiency in the Marma population.