Spectrum of β thalassemia mutations and their linkage to β‐globin gene haplotypes in the Indo‐Mauritians

The beta thalassemia alleles in 53 thalassemic Indo-Mauritian patients and their families consisting of 23 homozygous beta-thalassemia, 9 HbS/beta-thalassemia, 18 HbS/beta-thalassemia, 1 HbD/beta-thalassemia, I delta beta/beta-thalassemia and 1 HbH/beta-thalassemia from the island of Mauritius were studied. Characterization:by polymerase chain reaction-based reverse dot blot hybridization technique revealed that the IVS1-5 (G-->C) mutation accounted for 74% of the beta thalassemic alleles, while six other mutations occurred at much lower frequencies: HbE codon 26 (G-->A); 10.4%, codon 8/9 (+G); 3.5%, codon 30 (AGG-->ACG) also called IVSI (-1).G-->C; 3.5%,:codon 15 (G-->A); 3.5%, codon 41/42 (-CTTT); 2.4% and -28 (A-IG); 2.4%, Association:of these mutations to specific beta globin gene sequence framework and haplotype allowed to trace their ancestral link. These data are useful in future molecular screening of the,population in view of implementing a thalassemia prevention and control program in Mauritius. (C) 2000 Wiley-Liss, Inc.