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Published on: January 7, 2014
Histamine N-methyltransferase Thr105Ile is not associated with Parkinson's disease or essential tremor
Brett H Keeling1, Carles Vilariño-Güell, Alexandra I Soto-Ortolaza
1Department of Neuroscience, Mayo Clinic College of Medicine, Jacksonville, FL 32224, USA.
Abstract:
A functional variant in the Histamine N-Methyltransferase gene (HNMT - rs11558538) resulting in a threonine to isoleucine substitution (Thr105Ile) has been shown to impair histamine degradation. Two recent studies reported that the threonine allele of this polymorphism might be a risk factor for Parkinson disease (PD) and essential tremor (ET) development. Although PD and ET are considered different entities, they share some clinical and pathological features, suggesting a possible joint etiology. In this study we assess the role of the Thr105Ile variant in PD and ET development, genotyping the variant in a North American Caucasian PD and ET case-control series. Statistical analysis did not identify any significant association between this variant and PD or ET; therefore, our findings do not support the HNMT Thr105Ile variant as a factor in disease development or a genetic link between the disorders.
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