Expanded CAG Repeats in ATXN1, ATXN2, ATXN3, and HTT in the 1000 Genomes Project

Mov Disord. 2021 Feb;36(2):514-518. doi: 10.1002/mds.28341. Epub 2020 Nov 7.

Abstract

Background: Spinocerebellar ataxia types 1, 2, 3 and Huntington disease are neurodegenerative disorders caused by expanded CAG repeats.

Methods: We performed an in-silico analysis of CAG repeats in ATXN1, ATXN2, ATXN3, and HTT using 30× whole-=genome sequencing data of 2504 samples from the 1000 Genomes Project.

Results: Seven HTT-positive, 3 ATXN2-positive, 1 ATXN3-positive, and 6 possibly ATXN1-positive samples were identified. No correlation was found between the repeat sizes of the different genes. The distribution of CAG alleles varied by ethnicity.

Conclusion: Our results suggest that there may be asymptomatic small expanded repeats in almost 0.5% of these populations. © 2020 International Parkinson and Movement Disorder Society.

Keywords: 1KGP; ATXN1; ATXN2; ATXN3; CAG-repeat diseases; HTT; ataxia.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alleles
  • Ataxin-1 / genetics
  • Ataxin-2 / genetics
  • Ataxin-3 / genetics
  • Humans
  • Huntingtin Protein / genetics
  • Huntington Disease*
  • Repressor Proteins / genetics
  • Spinocerebellar Ataxias* / genetics
  • Trinucleotide Repeat Expansion / genetics
  • Trinucleotide Repeats / genetics

Substances

  • ATXN1 protein, human
  • ATXN2 protein, human
  • Ataxin-1
  • Ataxin-2
  • HTT protein, human
  • Huntingtin Protein
  • Repressor Proteins
  • ATXN3 protein, human
  • Ataxin-3