The use of the Amplification Refractory Mutation System (ARMS) as an effective and economical tool for prenatal diagnosis of β-thalassaemia in Malaysian subjects

Abstract

Molecular characterisation of 155 β-thalassaemia genes was carried out using the Amplification Refractory Mutation System (ARMS) and comprised of 101 chromosomes from the Chinese, 52 from the Malays and 2 from the Indians. A total of 14 mutations along the β-globin gene complex was analysed using the ARMS: -29 (A➔G),-28 (A➔G), Cap(+1) (A➔C), Cd 8/9 (+G), Cd 15 (G➔A), Cd 17 (A➔T), Cd 19 (A➔G), Cd 26 (Hb E) (G➔A), IVSl #1 (G➔T), IVSI #5 {G➔C), Cd 41-42 (-TCTT), Cd 71-72 (+A), IVSII #654 (C➔T) and the 619 bp deletion at the 3'-end of the β-gene. Our results indicate that using the ARMS at these 14 sites, prenatal diagnosis can be achieved in 96% of the Chinese couples and 84.6% of the Malay couples at risk for a β-thalassaemia major child. In the Chinese, 5 out of the 14 β-mutations (Cd 41-42, IVSII #654, -28 TATA Box, Cd 17 and Cd 71-72) accounted for 92% of β-thalassaemia in this ethnic group. The β-mutations in the Malays were found to be more heterogeneous. Three β-mutations (Hb E, IVSI #5 and IVSI # 1) accounted for 73.08% of β-thalassaemia and 6 other β-mutations (Cd 41-42, IVSII #654, Cd 8/9, Cd 19, CD 17, Cap (+1)) made up the remaining 11.52% of the identified mutations in this ethnic group.