Article Text

PDF
Paraoxonase promoter and intronic variants modify risk of sporadic amyotrophic lateral sclerosis
  1. Simon Cronin1,
  2. Matthew J Greenway3,
  3. Jochen H M Prehn2,
  4. Orla Hardiman1,4
  1. 1Department of Neurology, Beaumont Hospital, Dublin, Ireland
  2. 2Department of Physiology, Royal College of Surgeons in Ireland, Dublin, Ireland
  3. 3National Centre for Medical Genetics, Our Lady’s Hospital for Sick Children, Dublin, Ireland
  4. 4Department of Clinical Neurological Sciences, Royal College of Surgeons in Ireland, Dublin, Ireland
  1. Correspondence to:
 Dr Simon Cronin
 The Irish ALS Research Group, Department of Neurology, Beaumont Hospital, Dublin 9, Ireland; scronin{at}rcsi.ie

Abstract

Background: The paraoxonases, PON1–3, play a major protective role both against environmental toxins and as part of the antioxidant defence system. Recently, non-synonymous coding single nucleotide polymorphisms (SNPs), known to lower serum PON activity, have been associated with sporadic ALS (SALS) in a Polish population. A separate trio based study described a detrimental allele at the PON3 intronic variant INS2+3651 (rs10487132). Association between PON gene cluster variants and SALS requires external validation in an independent dataset.

Aims: To examine the association of the promoter SNPs PON1−162G>A and PON1−108T>C; the non-synonymous functional SNPs PON1Q192R and L55M and PON2C311S and A148G; and the intronic marker PON3INS2+3651A>G, with SALS in a genetically homogenous population.

Methods: 221 Irish patients with SALS and 202 unrelated control subjects were genotyped using KASPar chemistries. Statistical analyses and haplotype estimations were conducted using Haploview and Unphased software. Multiple permutation testing, as implemented in Unphased, was applied to haplotype p values to correct for multiple hypotheses.

Results: Two of the seven SNPs were associated with SALS in the Irish population: PON155M (OR 1.52, p = 0.006) and PON3INS2+3651 G (OR 1.36, p = 0.03). Two locus haplotype analysis showed association only when both of these risk alleles were present (OR 1.7, p = 0.005), suggesting a potential effect modification. Low functioning promoter variants were observed to influence this effect when compared with wild-type.

Conclusions: These data provide additional evidence that genetic variation across the paroxanase loci may be common susceptibility factors for SALS.

  • ALS, amyotrophic lateral sclerosis
  • HWE, Hardy–Weinberg equilibrium
  • LD, linkage diseqilibrium
  • PON, paraoxonase
  • SALS, sporadic amyotrophic lateral sclerosis
  • SNP, single nucleotide polymorphism

Statistics from Altmetric.com

Footnotes

  • Funding: This research was supported by a translational research grant from the Charitable Infirmary Charitable Trust

  • Competing interests: None.

Request permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.