Two novel SNPs in ATXN3 3' UTR may decrease age at onset of SCA3/MJD in Chinese patients

PLoS One. 2015 Feb 17;10(2):e0117488. doi: 10.1371/journal.pone.0117488. eCollection 2015.

Abstract

Spinocerebellar ataxia type 3 (SCA3), or Machado-Joseph disease (MJD), is an autosomal dominantly-inherited disease that produces progressive problems with movement. It is caused by the expansion of an area of CAG repeats in a coding region of ATXN3. The number of repeats is inversely associated with age at disease onset (AO) and is significantly associated with disease severity; however, the degree of CAG expansion only explains 50 to 70% of variance in AO. We tested two SNPs, rs709930 and rs910369, in the 3' UTR of ATXN3 gene for association with SCA3/MJD risk and with SCA3/MJD AO in an independent cohort of 170 patients with SCA3/MJD and 200 healthy controls from mainland China. rs709930 genotype frequencies were statistically significantly different between patients and controls (p = 0.001, α = 0.05). SCA3/MJD patients carrying the rs709930 A allele and rs910369 T allele experienced an earlier onset, with a decrease in AO of approximately 2 to 4 years. The two novel SNPs found in this study might be genetic modifiers for AO in SCA3/MJD.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 3' Untranslated Regions*
  • Adolescent
  • Adult
  • Age of Onset
  • Aged
  • Alleles
  • Asian People / genetics
  • Ataxin-3 / genetics*
  • China
  • Female
  • Gene Frequency
  • Genotype
  • Humans
  • Machado-Joseph Disease / genetics*
  • Male
  • Middle Aged
  • Mutation
  • Polymorphism, Single Nucleotide*
  • Young Adult

Substances

  • 3' Untranslated Regions
  • Ataxin-3

Grants and funding

This study was supported by the National Basic Research Program (973 Program) (Nos. 2012CB944601, 2012CB517902 and 2011CB510002 to Hong Jiang), the New Century Excellent Talents in University (No. NCET-10-0836 to Hong Jiang), the National Natural Science Foundation of China (Nos. 81410308019, 81471156, 81271260, 30971585 to Hong Jiang), Hunan Funds for Distinguished Young Scientists (No. 14JJ1008 to Hong Jiang), Xinjiang Natural Science Foundation (No. 201318101-4 to Hong Jiang), the Undergraduate Innovation Project of Central South University (No. YB13028, 201410533324 to Hong Jiang), Graduate Innovation Project of Central South University (No. 2014zzts078 to Zhao Chen) and High-Level Medical Personnel of Hunan Province 225 Project. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.