Tan JAMA1, Yap SF1, Tan KL1 and Thong MK2
1. Department of Allied Health Sciences, Faculty of Medicine, University of Malaya
2. Department of Paediatric, Faculty of Medicine, University of Malaya
CITATION: Tan JAMA, Yap SP, Tan KL, Thong MK. The use of the Amplification Refractory Mutation System ARMS as an effective and economical tool for prenatal diagnosis of β-thalassaemia in Malaysian subjects. International Medical Research Journal. 1998;2(2):65–8.
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. The ARMS, an allele-specific DNA amplification system which employs direct amplification of a gene sequence followed by simple agarose gel electrophoresis, was found to be an accurate, rapid and economical protocol for prenatal diagnosis for β-thalassaemia in the Malaysian population.
KEYWORDS: β-thalassaemia, prenatal diagnosis, ARMS, ethnic groups
