beta-Thalassaemia mutations and their linkage to beta-haplotypes in Tamil Nadu in southern India.
A study for screening of beta-thalassaemia mutations by the Amplification Refractory Mutation System (ARMS) and haplotyping by Polymerase Chain Reaction (PCR) was undertaken because there was a paucity of data in Tamil Nadu in Southern India and to initiate a comprehensive prenatal diagnosis programme. A total of 294 alleles were analysed to study the nature of the mutations, of which 146 were beta-thalassaemia alleles. Only four types of beta-thalassaemia mutations were recorded. Of these, 128 alleles were of the variant IVS-1 nt 5 (G-->C). Thirteen had the mutation codon 41/42 (del TCTT), four had the mutation codon 8/9 (insert G) and one had the 619 bp deletion at the 3' end of the gene. The most common mutation, IVS-1 nt 5 (G-->C), was strongly associated with a single haplotype although the association was not absolute. The population of Tamil Nadu in Southern India seems to be ideal for initiating a prenatal diagnosis programme based on direct detection of mutation by ARMS coupled with RFLP linkage analysis.
Venkatesan
R
R
Department of Genetics, Post Graduate Institute of Basic Medical Sciences, Taramani, Madras, India.
Sarkar
R
R
Old
J M
JM
D000483:Alleles; D001483:Base Sequence; D015342:DNA Probes; D008040:Genetic Linkage; D006239:Haplotypes; D006801:Humans; D007194:India; D008969:Molecular Sequence Data; D017354:Point Mutation; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D017086:beta-Thalassemia / Q000235:genetics*
D015342:DNA Probes