Mutación heterocigota, autosómica recesiva del gen RARS2 en una paciente colombiana de padres no consanguíneos / Autosomal recessive heterocygote mutation of the RARS2 gene in a colombian patient with non- consanguineous parents

Las nuevas metodologías de secuenciación masiva han permitido caracterizar e identificar variantes genéticas asociadas a diferentes patologías. En este trabajo se presenta el caso de una paciente con una mutación del gen RARS2 que codifica la enzima arginino-ARNt ligasa para la codificación de proteínas. Esta alteración genética se manifiesta en hipoplasia pontocerebelosa tipo 6, con una prevalencia de <1/1 000 0000, caracterizada por un cerebelo y un puente de menor tamaño asociados a un retraso grave en el neurodesarrollo. El análisis de caso permite un mejor conocimiento de enfermedades de origen genético, específicamente, de aquellas con patrones de herencia autosómicos recesivos de padres no consanguíneos. Su estudio sobre todo en lo relacionado con el ámbito familiar y socioeconómico, y su base genética, ayuda a una mejor calidad de vida de los pacientes y su familia.

The latest method of next-generation sequencing has allowed the characterization and identification of genetic variants associated to diverse pathologies. In this article, we present the case of female patient with a mutation of the RARS2 gene that encodes the enzyme for arginyl tRNA synthetase for coding of proteins. This genetic alteration manifests in pontocerebellar hypoplasia type 6, with a prevalence of <1/1,000,0000, characterized by a cerebellum and pons that are smaller in size and are associated with severe neurodevelopmental delay. The analysis of the case of this patient provides better knowledge of diseases of genetic origin; specifically, regarding genetic diseases of autosomal recessive patterns of inheritance from non-consanguineous parents. The impact of these studies; specially within the family, social, economic and genetic aspects helps provide a better quality of life for these patients and their family.

[Autosomal recessive heterocygote mutation of the RARS2 gene in a colombian patient with non- consanguineous parents]. / Mutación heterocigota, autosómica recesiva del gen RARS2 en una paciente colombiana de padres no consanguíneos.

The latest method of next-generation sequencing has allowed the characterization and identification of genetic variants associated to diverse pathologies. In this article, we present the case of female patient with a mutation of the RARS2 gene that encodes the enzyme for arginyl tRNA synthetase for coding of proteins. This genetic alteration manifests in pontocerebellar hypoplasia type 6, with a prevalence of<1/1,000,0000, characterized by a cerebellum and pons that are smaller in size and are associated with severe neurodevelopmental delay. The analysis of the case of this patient provides better knowledge of diseases of genetic origin; specifically, regarding genetic diseases of autosomal recessive patterns of inheritance from non-consanguineous parents. The impact of these studies; specially within the family, social, economic and genetic aspects helps provide a better quality of life for these patients and their family.

Las nuevas metodologías de secuenciación masiva han permitido caracterizar e identificar variantes genéticas asociadas a diferentes patologías. En este trabajo se presenta el caso de una paciente con una mutación del gen RARS2 que codifica la enzima arginino-ARNt ligasa para la codificación de proteínas. Esta alteración genética se manifiesta en hipoplasia pontocerebelosa tipo 6, con una prevalencia de<1/1 000 0000, caracterizada por un cerebelo y un puente de menor tamaño asociados a un retraso grave en el neurodesarrollo. El análisis de caso permite un mejor conocimiento de enfermedades de origen genético, específicamente, de aquellas con patrones de herencia autosómicos recesivos de padres no consanguíneos. Su estudio sobre todo en lo relacionado con el ámbito familiar y socioeconómico, y su base genética, ayuda a una mejor calidad de vida de los pacientes y su familia.

Expanding spectrum of RARS2 gene disorders: Myoclonic epilepsy, mental retardation, spasticity, and extrapyramidal features.

Pontocerebellar hypoplasia type 6 (PCH6) is an autosomal recessive mitochondrial disease, typically characterized by pontine atrophy, vermian hypoplasia, infantile encephalopathy, generalized hypotonia, and intractable seizures. The purpose of this study is to describe the seizures and other neurological manifestations of RARS2 gene mutations and to compare the clinical features with other causes of progressive myoclonic epilepsy. Detailed history, physical examination, and clinical and genetic work-up were performed in 2 siblings who presented with progressive myoclonic epilepsy. One sibling, a 20-year-old woman, and the other a 24-year-old man, had a homozygous missense variant (c.848T>A; p.Leu283Gln) in exon 10 of the RARS2 gene. The female patient had action and audiogenic myoclonic jerks, postural tremors, spastic dysarthria, and bradykinesia, and her male sibling had similar features with oculomotor apraxia. The RARS2 gene mutation can present with myoclonic epilepsy, mental retardation, and pyramidal and extrapyramidal features, and is an important differential for causes of progressive myoclonic epilepsy.