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Parkinsonism with a Hint of Huntington's from 29 CAG Repeats in HTT.

ABSTRACT: Huntington's disease is caused by at least 36 cytosine-adenine-guanine (CAG) repeats in an HTT gene allele, but repeat tracts in the intermediate range (27-35 repeats) also display a subtle phenotype. This patient had a slightly elongated CAG repeat tract (29 repeats), a prominent family history of Parkinson's disease (PD), and a clinical phenotype mostly consistent with PD, but early dystonia and poor levodopa response. Neurophysiological test results were more consistent with Huntington's disease (HD) than PD. It is suggested that the intermediate allele modulated the clinical phenotype of PD in this patient.

SUBMITTER: Jot S

PROVIDER: S-EPMC6826852 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature

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Parkinsonism with a Hint of Huntington's from 29 CAG Repeats in HTT.

Jot Sipilä S

Brain sciences 20190922 10

Huntington's disease is caused by at least 36 cytosine-adenine-guanine (CAG) repeats in an HTT gene allele, but repeat tracts in the intermediate range (27-35 repeats) also display a subtle phenotype. This patient had a slightly elongated CAG repeat tract (29 repeats), a prominent family history of Parkinson's disease (PD), and a clinical phenotype mostly consistent with PD, but early dystonia and poor levodopa response. Neurophysiological test results were more consistent with Huntington's dise ...[more]

PMID: 31546689

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