Polycythemia associated with a hemoglobinopathy.

Abstract
An abnormal hemoglobin, called Chesapeake, was associated with mild polycythemia in a Caucasian family. Blood from heterozygous carriers had an O2 affinity as great as that of umbilical cord blood. An increased O2 affinity was a property of purified hemoglobin Chesapeake. Hemoglobin Chesapeake differed from hemoglobin-A in substitution of leucine for arginine in the 92 amino-acid residue of the [alpha]-chain. Hypotheses are presented relating the altered function of hemoglobin Chesapeake to this discrete structural abnormality.