Haemoglobin Dhofar is linked to the codon 29 C-->T (IVS-1 nt-3) splice mutation which causes beta+ thalassaemia.
Investigations of a young man with apparent thalassaemia minor showed that he was a heterozygote for a rare abnormal haemoglobin variant, Hb Dhofar. The amino acid replacement is in the beta-globin chain (beta 58 Pro-->Arg) and is therefore not consistent with the observed proportion of Hb Dhofar, as in both this and the original case, it constituted only 15% of the total haemoglobin. We have determined the basis of the low expression of this mutant, which is due to its linkage to a thalassaemic splicing mutation on the same beta-globin gene at codon 29 (C-->T). The finding of this thalassaemia mutation linked to Hb Dhofar not only explains the low level of Hb Dhofar, but also provides evidence that the codon 29 C-->T, IVS-1 splice junction mutation causes a beta+ form of thalassaemia.
Williamson
D
D
Department of Haematology, University of Cambridge.
Brown
K P
KP
Langdown
J V
JV
Baglin
T P
TP
D001483:Base Sequence; D005260:Female; D005914:Globins / Q000235:genetics*; D006455:Hemoglobins, Abnormal / Q000235:genetics*; D006801:Humans; D008969:Molecular Sequence Data; D009154:Mutation; D016133:Polymerase Chain Reaction; D017086:beta-Thalassemia / Q000235:genetics*
D006455:Hemoglobins, Abnormal; C094465:hemoglobin Dhofar; D005914:Globins