The clinical phenotype of carriers of intermediate alleles in the huntingtin gene: A scoping review.

ABSTRACT: BackgroundHuntington's Disease (HD) is a hereditary neurodegenerative disorder caused by a cytosine-adenine-guanine (CAG) repeat expansion (CAG > 35) in the Huntingtin (HTT) gene. Intermediate alleles (IAs, CAG = 27-35) are generally not associated with HD. However, IA carriers with symptoms have been reported in literature.ObjectiveTo review the existing literature on IAs, in order to provide an overview of the clinical phenotype of IA carriers.MethodsPeer-reviewed articles published between 1993 and July 2024 from three databases (Embase, PubMed, and Web of Science) were included.ResultsIn case reports, a high percentage (90%) of IA carriers was reported to have symptoms (HD-related and -unrelated), or abnormalities in neuroimaging. Cohort studies also reported evidence of symptom

SUBMITTER: van Hofslot A 

PROVIDER: S-EPMC12847463 | biostudies-literature | 2026 Feb

REPOSITORIES: biostudies-literature