Characterization of chromosomes with hybrid genes for Hb Lepore-Washington, Hb Lepore-Baltimore, Hb P-Nilotic, and Hb Kenya.

This study concerns the characterization of chromosomes with hybrid genes for Hb Lepore-Washington (44 chromosomes), for Hb Lepore-Baltimore (5 chromosomes), for Hb P-Nilotic (8 chromosomes), and for Hb Kenya (7 chromosomes) by determining a relatively large number of restriction enzyme polymorphism. Two, and possibly three, different Hb Lepore-Washington chromosomes were identified by specific haplotypes, while the haplotype of the Hb Lepore-Baltimore chromosome had its own characteristic pattern. A likely conclusion is that the crossovers leading to the formation of these chromosomes have occurred as independent events within the populations. Chromosomes with the delta beta-Lepore-Washington hybrid gene maintained specific characteristics (such as increased Hb F levels in heterozygotes, and high or low G gamma values in this Hb F) which have been observed in normal individuals with chromosomes having comparable haplotypes. Only one haplotype was observed for each of the chromosomes carrying either the beta delta-P-Nilotic hybrid gene or the A gamma beta hybrid gene of Hb Kenya.