CHARACTERIZATION OF BETA-THALASSEMIA MUTATIONS IN 57 BETA-THALASSEMIAFAMILIES SEEN AT LUCKNOW

As an initial step towards establishing prenatal diagnostic service fo r beta-thalassaemia in the state of Uttar Pradesh, we have investigate d the prevalence of five common mutations reported from India in 57 fa milies, each with an index patient of thalassaemia major, by amplifica tion refractory mutation system (ARMS). Thirtyone of the 57 families ( 54.3%) hailed from Uttar Pradesh; 11 (19.3%) from Sindh in Pakistan, 6 (10.5%) from Punjab, 6 (10.5%) from North-West Pakistan and one each (1.8%) from Bengal, Madhya Pradesh and Bihar. In the 31 families from Uttar Pradesh, 29 were of beta-thalassaemia and 2 of HbE/beta-thalassa emia. IVS-1 nt 5 (G-C) mutation was the most common mutation in famili es native to Uttar Pradesh. This mutation was identified in 60 per cen t; (33 out of 55) of the obligate heterozygotes. Amongst the 43 obliga te heterozygote carriers originating from Western India, the prevalenc e of IVS-1 nt 5 (G-C) mutation was 46.5 per cent; 619 bp deletion 23.3 per cent; Co 8/9 (+G) mutation 11.6 per cent and Co 41/42 (-CTTT) mut ation 4.6 per cent. In 23.6 per cent of carriers from Uttar Pradesh an d 7.0 per cent of carriers from Western India, none of the 5 mutations tested were detected. IVS-1 nt 1 (G-T) mutation was found in one fami ly native to Sindh.