RESUMEN
BACKGROUND: A large hexanucleotide repeat expansion in C9orf72 has been identified as the most common genetic cause in familial amyotrophic lateral sclerosis and frontotemporal dementia. Rapid Eye Movement Sleep Behavior Disorder (RBD) is a sleep disorder that has been strongly linked to synuclein-mediated neurodegeneration. The aim of this study was to evaluate the role of the C9orf72 expansions in the pathogenesis of RBD. METHODS: We amplified the C9orf72 repeat expansion in 344 patients with RBD by a repeat-primed polymerase chain reaction assay. RESULTS: We identified two RBD patients carrying the C9orf72 repeat expansion. Most interestingly, these patients have the same C9orf72 associated-risk haplotype identified in 9p21-linked amyotrophic lateral sclerosis and frontotemporal dementia families. CONCLUSIONS: Our study enlarges the phenotypic spectrum associated with the C9orf72 hexanucleotide repeat expansions and suggests that, although rare, this expansion may play a role in the pathogenesis of RBD.
Asunto(s)
Expansión de las Repeticiones de ADN/genética , Proteínas/genética , Trastorno de la Conducta del Sueño REM/diagnóstico , Trastorno de la Conducta del Sueño REM/genética , Adulto , Anciano , Anciano de 80 o más Años , Proteína C9orf72 , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
Large repeat expansions in the C9orf72 gene were recently reported to be a major cause of familial amyotrophic lateral sclerosis and frontotemporal dementia. Given some of the clinical and pathologic overlap between these 2 diseases and Parkinson's disease, we sought to evaluate the presence of these expansions in a cohort of French-Canadian patients with Parkinson's disease. No pathologic expansion was found in our cohort of patients suggesting that C9orf72 repeat expansions do not play a major role in the pathogenesis of Parkinson's disease.