Homozygous Sickle-cell Anaemia Arising from two Different Haemoglobins S

Abstract
In a Nilotic family in Uganda, independent segregation of Hbs A, S, and Stanleyville-II (Sta-n) was found. The Hb Sta-n was identified as an [alpha]-chain mutant with a mutation in the a-chain in the region of amino-acid residues 93-139. In the whole family 6 of the 9 possible hemoglobin phenotypes were found : Hb A, Hb A + S, Hb A + Sta-n, Hb S, Hb A + S + Sta-II+ (Sta-II/S), and Hb S+ (Sta-II/S) (the propositus). The proposltus presents a new type of homozygous sickle-cell anemia.