RESUMEN
BACKGROUND AND OBJECTIVE: The aim of this study was to determine the molecular defects of heterozygous beta thalassaemia and to ascertain their distribution in Lanzarote. PATIENTS AND METHOD: Molecular characterization was achieved by real time polymerase chain reaction (RT-PCR LightCycler, Roche), PCR-ARMS (PCR-amplification reaction mutations system) and DNA sequencing on an automated DNA sequencer. RESULTS: Two hundred forty-three heterozygous beta thalassaemia carriers were included between July 1991 and February 2007. RT-PCR detected the molecular defect in 81% of the beta thalassaemia chromosomes analyzed [113 codon CD 39 (C --> T); 41 IVS-1-nt-110 (G --> A), 25 IVS 1-nt-1 (G --> A) and 19 IVS 1-nt-6 (T --> C)]. The remaining 12 molecular defects included the deletion 619 bp (7.8%) and the mutations -28 (A --> G), IVS1-nt-2 (T --> G), CD 41/42 (-TTCT), CD 8/9 (+G), CD 51 (-C), CD 22 (G --> T) and CD 24 (T --> A), CD 67 (-TG) and the novel mutation CD 20/21-TGGA. CONCLUSIONS: The distribution of the mutations is similar to that found in the Mediterranean area. The increasing migratory flow received in the Canary Islands may explain the emergence of new mutations not reported before in our area.
Asunto(s)
Heterocigoto , Talasemia beta/epidemiología , Talasemia beta/genética , Áreas de Influencia de Salud , Estudios Transversales , Mutación del Sistema de Lectura/genética , Eliminación de Gen , Frecuencia de los Genes , Humanos , Prevalencia , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , España/epidemiología , Talasemia beta/sangreRESUMEN
Fundamento y objetivo: Caracterizar los defectos moleculares y estudiar su distribución en los portadores de betatalasemia de Lanzarote. Pacientes y método: El estudio molecular del gen beta de la globina se llevó a cabo con la técnica de reacción en cadena de la polimerasa (PCR) en tiempo real (RT-PCR LyghtCycler, Roche), PCR con amplificación de alelos específicos (PCR-ARMS) y secuenciación automática del ADN del gen beta de la globina. Resultados: Se incluyó en el estudio a 243 portadores diagnosticados de betatalasemia heterocigota entre julio de 1991 y febrero de 2007. La RT-PCR identificó la lesión molecular en el 81% de los cromosomas [113 codón CD 39 (C * T); 41 IVS-1-nt-110 (G * A), 25 IVS 1-nt-1 (G * A) y 19 IVS 1-nt-6 (T * C)]. Las 12 alteraciones moleculares restantes incluyeron la deleción 619 bp (7,8%) y las mutaciones 28 (A * G), IVS1-nt-2 (T * G), CD 41/42 (TTCT), CD 8/9 (+G), CD 51 (C), CD 22 (G * T), CD 24 (T * A), CD 67 (TG), además de una nueva mutación CD 20/21-TGGA. Conclusiones: La distribución de las mutaciones de la betatalasemia heterocigota en Lanzarote es similar a la descrita en la zona mediterránea. El aumento de los flujos migratorios a la comunidad canaria puede explicar la presencia de mutaciones no descritas antes en nuestra comunidad
Background and objective: The aim of this study was to determine the molecular defects of heterozygous b thalassaemia and to ascertain their distribution in Lanzarote. Patients and method: Molecular characterization was achieved by real time polymerase chain reaction (RT-PCR LightCycler, Roche), PCR-ARMS (PCR-amplification reaction mutations system) and DNA sequencing on an automated DNA sequencer. Results: Two hundred forty-three heterozygous b thalassaemia carriers were included between July 1991 and February 2007. RT-PCR detected the molecular defect in 81% of the b thalassaemia chromosomes analyzed [113 codon CD 39 (C * T); 41 IVS-1-nt-110 (G * A), 25 IVS 1-nt-1 (G * A) and 19 IVS 1-nt-6 (T * C)]. The remaining 12 molecular defects included the deletion 619 bp (7.8%) and the mutations 28 (A * G), IVS1-nt-2 (T * G), CD 41/42 (TTCT), CD 8/9 (+G), CD 51 (C), CD 22 (G * T) and CD 24 (T * A), CD 67 (TG) and the novel mutation CD 20/21-TGGA. Conclusions: The distribution of the mutations is similar to that found in the Mediterranean area. The increasing migratory flow received in the Canary Islands may explain the emergence of new mutations not reported before in our area