Determination of the breakpoint and molecular diagnosis of a common alpha-thalassaemia-1 deletion in the Indian population.
The previously described South African type alpha-thalassaemia-1 mutation was identified in Indian HbH patients using a polymerase chain reaction (PCR) strategy. A multiplex PCR assay was devised to detect heterozygotes and homozygotes. This alpha-thalassaemia-1 mutation was found to be the commonest determinant causing HbH disease in this population. In one family this mutation was found in combination with a novel splice donor mutation alpha2 IVS I-1 (G-->A). Characterization of the breakpoint junction sequence revealed, in addition to a 23 kb deletion, that there was an addition of approximately 160 bp bridging the breakpoints. Similar to other deletions in the alpha-globin gene cluster, there is an Alu repeat-mediated mechanism for the origin of the deletion.
Shaji
R V
RV
Department of Haematology, Christian Medical College, Vellore, India. rvshaji@cmcvellore.ac.in
Eunice
S E
SE
Baidya
S
S
Srivastava
A
A
Chandy
M
M
D000328:Adult; D001483:Base Sequence; D005260:Female; D017353:Gene Deletion; D005914:Globins / Q000235:genetics*; D006579:Heterozygote; D006801:Humans; D007194:India; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D017354:Point Mutation; D016133:Polymerase Chain Reaction / Q000379:methods; D022821:RNA Splice Sites; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D017085:alpha-Thalassemia / Q000235:genetics*
D022821:RNA Splice Sites; D005914:Globins