Haemoglobin Sydney: β67 (EII) Valine→ Alanine : an Emerging Pattern of Unstable Haemoglobins

SEVERAL abnormal haemoglobins have recently been found in patients with inclusion body haemolytic anaemias 1 , and have been called unstable because they form precipitates more readily than haemoglobin A when warmed to 50° C. We now report the identification of the structural abnormality in one of these haemoglobins—haemoglobin Sydney—the haematology and the family study of which have already been described 2 .