Polycythaemia associated with a new haemoglobin variant: haemoglobin Palmerston North beta 23 (B5) val----phe

A new haemoglobin variant, with increased oxygen affinity, has been identified in a patient with a long history of polycythaemia. This new haemoglobin, Hb Palmerston North, has an amino acid substitution of valine to phenylalanine at position beta 23 (B5). The increased oxygen affinity is accompanied by a decrease in globin stability which was responsible for the laboratory detection of the haemoglobinopathy.