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Journal of Neurology

, Volume 265, Issue 9, pp 2149–2151 | Cite as

Telomere length as a modifier of age-at-onset in Huntington disease: a two-sample Mendelian randomization study

  • N. Ahmad Aziz
  • Patrick Weydt
Letter to the Editors

Dear Sirs,

Huntington disease (HD) is an autosomal dominant inherited neurodegenerative disorder caused by a CAG repeat expansion in exon 1 of the HTT gene. Despite a strong inverse association between mutant HTT CAG repeat size and age-at-onset, there is a large residual variability in disease onset which is attributable to other modifying genetic or environmental factors [1]. Telomeres are repetitive sequences of nucleotides at the end of chromosomes protecting them from degeneration or fusion with neighboring chromosomes. Recently, shortened telomeres were reported in HD patients compared to matched controls [2]. Because shortened telomeres have been associated with an increased risk of several neuropsychiatric and neurodegenerative disorders [3], we hypothesized that telomere length could also be a modifier of age-at-onset in HD.

We performed a two-sample Mendelian randomization (MR) study; a recently developed statistical method which allows assessment of the effects of an...

Notes

Compliance with ethical standards

Conflicts of interest

Dr Aziz and Dr Weydt report no conflicts of interest.

References

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    Kota LN, Bharath S, Purushottam M et al (2015) Reduced telomere length in neurodegenerative disorders may suggest shared biology. J Neuropsychiatry Clin Neurosci 27(2):e92–e96CrossRefPubMedGoogle Scholar
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    Zhan Y, Song C, Karlsson R et al (2015) Telomere length shortening and Alzheimer disease—a Mendelian randomization study. JAMA Neurol 72(10):1202–1203CrossRefPubMedGoogle Scholar
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    Davey Smith G, Hemani G (2014) Mendelian randomization: genetic anchors for causal inference in epidemiological studies. Hum Mol Genet 23(R1):R89–R98CrossRefPubMedPubMedCentralGoogle Scholar
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    Hemani G, Zheng J, Wade KH et al (2016) MR-base: a platform for systematic causal inference across the phenome using billions of genetic associations. bioRxiv.  https://doi.org/10.1101/078972 Google Scholar

Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.German Centre for Neurodegenerative Diseases (DZNE)BonnGermany
  2. 2.Department of Neurodegenerative Diseases and GerontopsychiatryUniversity of Bonn Medical CentreBonnGermany

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