Original Communication - Detection of two rare β-thalassemia mutations [-90 (C → T) and CD 26 (C →T)] among Indians

BACKGROUND: β -Thalassemia (β-thal) is present in practically every caste group in Indians. Molecular characterization of β-thal in these groups has revealed an extremely heterogeneous picture. AIM: To identify all the mutations and to detect the novel mutations using a versatile mutation detection technique. MATERIALS AND METHODS: Denaturing gradient gel electrophoresis (DGGE) has been established to scan the entire β-globin gene to localize the mutation followed by DNA sequencing for characterization. The DNA samples from two families referred to us either for prenatal diagnosis or for DNA studies were studied. RESULTS: Atypical DGGE patterns in fragments B & A indicating the presence of the mutation, have been detected in both the families. DNA sequencing revealed two rare patterns fragments with patterns in fragments β-thal mutations [CD 26 (C→T) and -90 (C →T)]. CONCLUSION: DGGE is a useful mutation detection technique to identify β-thal mutations among the heterogeneous Indian population

Original Communication - Detection of two rare β-thalassemia mutations [-90 (C → T) and CD 26 (C →T)] among Indians

BACKGROUND: β -Thalassemia (β-thal) is present in practically every caste group in Indians. Molecular characterization of β-thal in these groups has revealed an extremely heterogeneous picture. AIM: To identify all the mutations and to detect the novel mutations using a versatile mutation detection technique. MATERIALS AND METHODS: Denaturing gradient gel electrophoresis (DGGE) has been established to scan the entire β-globin gene to localize the mutation followed by DNA sequencing for characterization. The DNA samples from two families referred to us either for prenatal diagnosis or for DNA studies were studied. RESULTS: Atypical DGGE patterns in fragments B & A indicating the presence of the mutation, have been detected in both the families. DNA sequencing revealed two rare patterns fragments with patterns in fragments β-thal mutations [CD 26 (C→T) and -90 (C →T)]. CONCLUSION: DGGE is a useful mutation detection technique to identify β-thal mutations among the heterogeneous Indian population

Red Cell Genetic Abnormalities, b-Globin Gene Haplotypes, and APOB Polymorphism in the Great Andamanese, A Primitive Negrito Tribe of Andaman and Nicobar Islands, India

The Great Andamanese are a primitive Negrito tribe of the Andaman and Nicobar Islands, India, with a total population of 37. We studied 29 individuals from eight families from this population for abnormal hemoglobins, G6PD deficiency, DNA haplotypes, and apolipoprotein B (APOB, gene) polymorphism. Hb E was detected in five individuals, the prevalence of Hb E heterozygotes being 14.3%. One individual had b-thalassemia trait. One female was G6PD deficient and showed the G6PD Orissa mutation. Haplotype analysis of the b-globin gene cluster showed that the bE chromosomes were linked to two haplotypes (– – – – – + + and + + – + + + +) representing the framework 1 gene, whereas the bA chromosomes showed eight different haplotypic patterns corresponding to framework 1 and 3 genes. APOB polymorphism analysis showed that the 631-base-pair (bp) allele was the predominant one with a high homozygosity rate, which could be due to the higher rate of inbreeding in this isolated group. The presence of Hb E and our findings on haplotype analysis supports the hypothesis that the Great Andamanese are reasonably believed to be the surviving representatives of the Negrito race that once flourished in the entire Southeast Asian region in ancient times