Premium
The molecular basis of alpha thalassaemia in a South African population
Author(s) -
Mathew C. G. P.,
Rousseau J.,
Rees J. S.,
Harley E. H.
Publication year - 1983
Publication title -
british journal of haematology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.907
H-Index - 186
eISSN - 1365-2141
pISSN - 0007-1048
DOI - 10.1111/j.1365-2141.1983.tb01228.x
Subject(s) - haplotype , globin , genetics , population , biology , alpha (finance) , hemoglobinopathy , alpha globulin , alpha thalassemia , gene , chromosome , microbiology and biotechnology , allele , hemolytic anemia , genotype , medicine , immunology , nursing , construct validity , environmental health , patient satisfaction
S ummary . We have investigated the molecular basis of α thalassaemia in the so‐called ‘Cape Coloured’population of Cape Town. DNA from 17 cases was analysed by Southern blotting and hybridization with an α globin complementary DNA probe. Three types of α thalassaemia genetic determinants were detected: the 3·5 kb deletion which inactivates one α globin gene per chromosome (‐α/ haplotype), a much larger deletion which removes both α globin genes (––/ haplotype), and a non‐deletion determinant which leaves both α globin genes intact. The interaction of these determinants with each other or with the normal chromosome (αα/) produced the phenotypes α thalassaemia silent carrier, α thalassaemia trait and Hb H disease. All cases of the ‐α/ haplotype result from the rightward deletion which removes the Bgl II site between the duplicated α globin genes. The predominance of the ‐α/ haplotype (21 out of the 28 α thalassaemia determinants) over the ––/ haplotype is consistent with the low incidence of Hb H disease and the apparent absence of Hb Bart's hydrops fetalis in this population group.