[Autism, epilepsy and genetics]. / Autismo, epilepsia y genética.

INTRODUCTION: The rate of epilepsy in autism is higher than in other developmental disorders and estimates point to a frequency range of between 7% and 42%. Between 40% and 47% of autistic children suffer from clinical epilepsy. Onset of epilepsy may occur at any age. DEVELOPMENT: During the ontogenesis of the nervous system, if the maturing process is upset by some epileptogenic phenomenon, the consequences on the consolidation of the emerging cognitive functions can be severe. Epileptiform discharges can occur although clinical seizures are absent, but nevertheless they still have an effect on the maturing process. Between 10% and 50% of autistic children undergo a regression of acquired behaviour following a period of normal development. The absence of clinical seizures during regression does not rule out the epileptogenic origin of the regressive process. CONCLUSIONS: The relation between pervasive developmental disorders and epilepsy, epileptiform activity and subclinical seizures can be explained from a neurobiological point of view, on the one hand, by an imbalance between the excitatory system -glutamate- and the inhibitory system -gamma-aminobutyric acid (GABA)- in key points in the cerebral cortex and, on the other, by means of molecular genetic studies and studies of candidate genes (FOXP2, WNT2, subunits of GABA receptors, neuroligins, ARX, SCN1A, SCN2A, MECP2, CDKL5 and DLX5).

Autismo, epilepsia y genética / Autism, Epilepsy and Genetics

Introducción. La tasa de epilepsia en el autismo es mayor que en otros trastornos del desarrollo, y se estima en un rango de frecuencia del 7 al 42%. Entre el 40 y el 47% de los niños autistas sufre epilepsia clínica. El inicio de la epilepsia puede darse a cualquier edad. Desarrollo. Durante la ontogénesis del sistema nervioso, si el proceso madurativo se ve interferido por un fenómeno epileptógeno, las consecuencias pueden ser graves para la consolidación de las funciones cognitivas emergentes. Las descargas epileptiformes pueden darse en ausencia de crisis clínicas, pero afectando de igual manera al proceso madurativo. Entre el 10 y el 50% de los niños autistas sufre una regresión de la conducta adquirida después de un período de desarrollo normal. La ausencia de crisis clínicas durante la regresión no descarta el origen epileptogénico del proceso regresivo. Conclusiones. Se puede explicar la relación entre los trastornos generalizados del desarrollo y la epilepsia, la actividad epileptiforme y las crisis subclínicas desde un punto de vista neurobiológico, por un lado, mediante un desequilibrio entre el sistema excitador –glutamato– y el sistema inhibidor –ácido gamma-aminobutírico (GABA)– en puntos claves del córtex cerebral y, por otro lado, mediante los estudios de genética molecular y estudio de genes candidatos (FOXP2, WNT2, subunidades de los receptores GABA, neuroliginas, ARX, SCN1A, SCN2A, MECP2, CDKL5 y DLX5) (AU)

Introduction. The rate of epilepsy in autism is higher than in other developmental disorders and estimates point to a frequency range of between 7% and 42%. Between 40% and 47% of autistic children suffer from clinical epilepsy. Onset of epilepsy may occur at any age. Development. During the ontogenesis of the nervous system, if the maturing process is upset by some epileptogenic phenomenon, the consequences on the consolidation of the emerging cognitive functions can be severe. Epileptiform discharges can occur although clinical seizures are absent, but nevertheless they still have an effect on the maturing process. Between 10% and 50% of autistic children undergo a regression of acquired behaviour following a period of normal development. The absence of clinical seizures during regression does not rule out the epileptogenic origin of the regressive process. Conclusions. The relation between pervasive developmental disorders and epilepsy, epileptiform activity and subclinical seizures can be explained from a neurobiological point of view, on the one hand, by an imbalance between the excitatory system –glutamate– and the inhibitory system –gamma-aminobutyric acid (GABA)– in key points in the cerebral cortex and, on the other, by means of molecular genetic studies and studies of candidate genes (FOXP2, WNT2, subunits of GABA receptors, neuroligins, ARX, SCN1A, SCN2A, MECP2, CDKL5 and DLX5) (AU)