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Disomía paterna uniparental en el síndrome de Angelman
S Malcolm1, J Clayton-Smith, M Nichols
1Mothercare Department of Paediatric Genetics, Institute of Child Health, London, UK.
Lancet (London, England)
|March 23, 1991
Resumen
El síndrome de Angelman y el síndrome de Prader-Willi, vinculados a las deleciones del cromosoma 15, demuestran la impresión genómica. La disomía uniparental del cromosoma 15 causa fenotipos distintos, lo que pone de relieve los efectos de los genes parentales.
Área de la Ciencia:
- Genética La genética.
- Biología del desarrollo Biología del desarrollo.
- Fisiología Humana Fisiología Humana.
Sus antecedentes:
- El síndrome de Angelman y el síndrome de Prader-Willi son trastornos del desarrollo neurológico distintos.
- Ambos síndromes están asociados con deleciones en la región 15q11-13 del cromosoma 15.
- El origen parental de la supresión determina el síndrome específico.
Objetivo del estudio:
- Para investigar la base genética del síndrome de Angelman y el síndrome de Prader-Willi.
- Para explorar el papel de la impresión genómica en los trastornos del cromosoma 15.
- Para analizar los casos de disomía uniparental en el síndrome de Angelman.
Principales métodos:
- Fenotipado clínico de pacientes con el síndrome de Angelman y el síndrome de Prader-Willi.
- Análisis genético para identificar deleciones y disomía uniparental del cromosoma 15.
- Comparación de los efectos fenotípicos asociados con la herencia materna y paterna del cromosoma 15.
Principales resultados:
- El síndrome de Angelman está típicamente asociado con deleciones maternas o disomía paterna del cromosoma 15.
- El síndrome de Prader-Willi se asocia típicamente con deleciones paternas o disomía materna del cromosoma 15.
- Dos pacientes con el síndrome de Angelman exhibieron disomía paterna uniparental del cromosoma 15.
Conclusiones:
- La impresión genómica juega un papel crítico en el desarrollo humano, con genes que exhiben una expresión diferencial basada en el origen parental.
- La disomía uniparental del cromosoma 15 da como resultado fenotipos clínicos distintos, lo que subraya la importancia de la impresión.
- La herencia de dos copias del cromosoma 15 de un solo padre no asegura un desarrollo normal, apoyando aún más los mecanismos de impresión.
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