DISTRIBUTION OF BETA-THALASSEMIA MUTATIONS IN 3 ASIAN INDIAN POPULATIONS WITH DISTANT GEOGRAPHICAL LOCATIONS

We have identified the beta-thalassemia alleles in 47 pediatric patien ts with transfusion-dependent thalassemia major from a clinic in New D elhi and in 105 heterozygous relatives. Surprisingly, only five mutati ons were present in 94 beta-thalassemia chromosomes with frequencies f rom 10 to 32%. This observation greatly facilitated the initiation of a prenatal diagnostic program. Similar studies were conducted for seve n Asian Indian patients from Calgary, Canada, seven Asian Indian patie nts from Durban, South Africa, and from heterozygous relatives, and pe rsons with a beta-thalassemia trait who were not related. Besides beta -thalassemia alleles, common to Asian Indian beta-thalassemia patients , some unexpected alleles were observed in the patients from South Afr ica, including a newly discovered frameshift at codon 15 (-T).