Candidate gene analysis suggests a role for fatty acid biosynthesis and regulation of the complement system in the etiology of age-related maculopathy

Hum Mol Genet. 2005 Jul 15;14(14):1991-2002. doi: 10.1093/hmg/ddi204. Epub 2005 Jun 1.

Abstract

Age-related maculopathy (ARM) is a leading cause of visual impairment in elderly Americans and is a complex genetic disorder. Hypothesized pathways for the etiology of ARM include cholesterol and lipoprotein metabolism and transport, extracellular matrix integrity, oxidative stress and inflammatory/immunologic processes. This study investigates 21 polymorphisms within 15 candidate genes whose products function within these pathways by performing family and case-control genetic association studies using clearly affected familial cases (n=338 families, 796 individuals), clearly affected, unrelated sporadic cases (n=196) and clearly unaffected, unrelated controls (n=120). Two genes demonstrated significant association with ARM status. A Met299Val variant in the elongation of very long chain fatty acids-like 4 (ELOVL4) gene was significantly associated with ARM in the case-control allele (P=0.001), case-control genotype (P=0.001) and case-control family (P<0.0001) tests. A Tyr402His variant in exon 9 in the complement factor H (CFH) gene was also significantly associated with ARM in the case-control allele (P<0.0001), case-control genotype (P<0.0001) and case-control family (P<0.0001) tests. All of these results remain significant after adjusting for false discovery rates to control for the impact of multiple testing. In addition, the CFH variant appears to play a role in exudative and atrophic disease, whereas the ELOVL4 variant may play a greater role in exudative disease in our population. These results support a potential role for multiple pathways in the etiology of ARM, including pathways involved with fatty acid biosynthesis and the complement system.

Publication types

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

MeSH terms

  • Aging
  • Alleles
  • Base Sequence
  • Case-Control Studies
  • Complement System Proteins / physiology*
  • DNA Primers
  • Fatty Acids / biosynthesis*
  • Gene Frequency
  • Humans
  • Macular Degeneration / etiology
  • Macular Degeneration / genetics*
  • Phenotype
  • Polymorphism, Genetic

Substances

  • DNA Primers
  • Fatty Acids
  • Complement System Proteins