RESUMEN
We report four rare beta-thalassemia (thal) mutations, viz. AATAAA --> AACAAA [polyadenylation (poly A) site mutation]. IVS-II-745 (C --> G), codon 121 (G --> T) and IVS-II-1 (G --> A), detected by denaturing gradient gel electrophoresis (DGGE) among Indians. Of these, the poly A site mutation has been found in combination with deletional delta(beta)-thal in one case, and with the IVS-1-5 (G --> C) mutation in another. Two DGGE patterns, corresponding to the same IVS-II-1 (G --> A) mutation, were seen in one family. Framework (FW) analyses in family studies have shown that the poly A site mutation is associated with FW-1, while both the codon 121 (G --> T) and IVS-II-1 (G --> A) mutations are associated with FW-2. Denaturing gradient gel electrophoresis facilitates the screening of rare beta-thal mutations in the diverse Indian population with its many ethnic groups, covering a vast geographic territory.
Asunto(s)
Mutación Puntual , Señales de Poliadenilación de ARN 3'/genética , Talasemia beta/genética , Adulto , Niño , Preescolar , Análisis Mutacional de ADN , Electroforesis en Gel de Poliacrilamida , Femenino , Humanos , India , MasculinoRESUMEN
beta-Thalassemia (thal) is an autosomal recessive disorder with a prevalence of 2-3% in Indians, while hemophilia A is X-linked with a prevalence of 1 in 5,000-10,000 male births. The chances of both these disorders being present together is extremely rare (1 in 250,000). We report an interesting consanguineous family from Western India with a combination of these two disorders, which was referred to us for prenatal diagnosis.