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La asociación entre las mutaciones en un transportador de la hormona tiroidea y la severa retardación psicomotora
Edith C H Friesema1, Annette Grueters, Heike Biebermann
1Department of Internal Medicine, Erasmus MC, Rotterdam, Netherlands.
Lancet (London, England)
|October 19, 2004
Resumen
Las mutaciones en el gen del transportador monocarboxilato 8 (MCT8) causan retraso psicomotor ligado al X. Este defecto afecta la entrada de la hormona tiroidea (T3) en las neuronas, afectando el desarrollo y el metabolismo del cerebro.
Área de la Ciencia:
- Genética La genética.
- Endocrinología Endocrinología.
- La neurociencia es la neurociencia.
Sus antecedentes:
- El transportador monocarboxilato 8 (MCT8) es crucial para el transporte de la hormona tiroidea.
- El gen MCT8 se encuentra en el cromosoma X.
Objetivo del estudio:
- Investigar el papel de las mutaciones MCT8 en el retraso psicomotor severo.
- Para determinar si los defectos de MCT8 conducen a niveles elevados de triiodotironina (T3) en el suero.
Principales métodos:
- Análisis de la secuencia de codificación MCT8 en cinco niños no relacionados con retraso psicomotor.
- Utilizó la reacción en cadena de la polimerasa (PCR) y la secuenciación directa de exones MCT8.
- Identificó deleciones genéticas y mutaciones de mal sentido.
Principales resultados:
- Identificó deleciones de genes (2.4 kb y 24 kb) en dos pacientes.
- Se detectaron mutaciones de mal sentido (Ala150Val, Arg171stop, Leu397Pro) en tres pacientes.
- Se observó retraso psicomotor grave y altas concentraciones séricas de T3.
Conclusiones:
- Un nuevo síndrome de retraso psicomotor ligado al X está asociado con los defectos del MCT8.
- La entrada deteriorada de T3 en las neuronas debido a un transporte defectuoso de MCT8 interrumpe la acción y el metabolismo de la hormona tiroidea.
- Las mutaciones MCT8 representan una causa significativa de trastornos del desarrollo neurológico.
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