C9orf72 expansions are the most common genetic cause of Huntington disease phenocopies.

ABSTRACT:

Objective

In many cases where Huntington disease (HD) is suspected, the genetic test for HD is negative: these are known as HD phenocopies. A repeat expansion in the C9orf72 gene has recently been identified as a major cause of familial and sporadic frontotemporal lobar degeneration and amyotrophic lateral sclerosis. Our objective was to determine whether this mutation causes HD phenocopies.

Methods

A cohort of 514 HD phenocopy patients were analyzed for the C9orf72 expansion using repeat primed PCR. In cases where the expansion was found, Southern hybridization was performed to determine expansion size. Clinical case notes were reviewed to determine the phenotype of expansion-positive cases.

Results

Ten subjects (1.95%) had the expansion, making it the most common id

SUBMITTER: Hensman Moss DJ 

PROVIDER: S-EPMC3929197 | biostudies-literature | 2014 Jan

REPOSITORIES: biostudies-literature