[HbM Erlangen: alpha2beta263(e7) tyr. New mutation with haemolysis and NADH-methaemoglobin reductase deficiency (author's transl)].

Report on a further hemoglobin M variant, discovered in a boy with congenital cyanosis. Chemical analysis of hemoglobin structure revealed indentity with HbM Saskatoon (= beta63 His leads to Tyr). The abnormal hemoglobin is characterized by normal oxygen transport function. The observed slight constant hemolysis is thought to be due to increased instability of the abnormal hemoglobin molecule. In addition to the hemoglobin anomaly, the activity of NADH-methemoglobin reductase was reduced by approximately 40% of normal. None of the parents presented with an abnormal hemoglobin, indicating that the occurrence of hemoglobin M Erlangen is most likely the result of a new mutation.