Hemoglobin Kenya, the product of a gamma-beta fusion gene: studies of the family.

Abstract

Recently, we reported the discovery of a new hemoglobin variant, Hb Kenya, in a 26-year-old Kenyan of the Nilotic Luo tribe [1]. Chemical characterization of the non-a chain of this hemoglobin showed that the amino terminal segment has the sequence of the y chain of fetal hemoglobin (Hb F) and the carboxy terminal segment that of the /8 chain of Hb A. It was concluded that the non-a chain of Hb Kenya is the product of a hybrid gene that has been formed by nonhomologous crossing over within gene loci. On the basis primarily of electrophoretic and hematological observations (A. G. Kendall, unpublished), the propositus was originally diagnosed as a heterozygote for Hb S and the hereditary persistence of Hb F (HPFH). Because of the discovery of Hb Kenya in the propositus, a reevaluation of his condition and that of members of his immediate family was highly desirable. This report describes the results of these studies as well as additional chemical evidence to support the y-)3 structure of the non-a chain of Hb Kenya.