The Kunama and Nara tribes inhabit north-west Eritrea, and are both of somewhat negroid appearance. Blood samples were tested for blood groups of seven systems, for glucose-6-phosphate dehydrogenase deficiency and for abnormal haemoglobins.
Their blood groups show them to be of mixed Caucasoid-Negroid origin with rather more negroid marker genes than most of the surrounding populations. Abnormal haemoglobins were absent but males of both tribes included about 4 per cent of cases of glucose-6-phosphate dehydrogenase deficiency, and there were some cases of raised levels of haemoglobin A2(possibly due to thalassaemia) and of foetal haemoglobin in adults. Thalassaemia and glucose-6-phosphate dehydrogenase deficiency are likely to have been favoured by natural selection in an environment which was formerly malarious, with a high proportion of Plasmodium falciparum infection.
Their blood groups show them to be of mixed Caucasoid-Negroid origin with rather more negroid marker genes than most of the surrounding populations. Abnormal haemoglobins were absent but males of both tribes included about 4 per cent of cases of glucose-6-phosphate dehydrogenase deficiency, and there were some cases of raised levels of haemoglobin A2(possibly due to thalassaemia) and of foetal haemoglobin in adults. Thalassaemia and glucose-6-phosphate dehydrogenase deficiency are likely to have been favoured by natural selection in an environment which was formerly malarious, with a high proportion of Plasmodium falciparum infection.