Methylenetetrahydrofolate reductase genetic polymorphisms in patients with cataract

Am J Ophthalmol. 2005 Nov;140(5):932-4. doi: 10.1016/j.ajo.2005.05.026.


Purpose: Hyperhomocysteinemia is commonly associated with polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) gene. The level of homocysteine can be lowered by dietary intake of folate. A protective effect of folate supplementation has been reported against cataract. Here we investigate MTHFR polymorphisms in human cataract.

Design: Retrospective case-control association study.

Methods: Patients with nuclear (n = 77), cortical (n = 155), posterior subcapsular (n = 119), and mixed (n = 151) cataract, and 187 controls were analyzed for the MTHFR 677C-->T and 1298A-->C polymorphisms using minisequencing technique.

Results: The wild-type MTHFR 677CC/1298AA genotype was strongly overrepresented among cataract cases (P = .003). This effect was most pronounced in the mixed cataract group (P < .001). Hyperhomocysteinemia-associated genotypes had similar frequencies in cataract and control groups.

Conclusions: The previously reported protective effect of folate against cataract is not due to overrepresentation of hyperhomocysteinemia-associated MTHFR genotypes. Instead, the strong predominance of wild-type MTHFR in cataract may suggest impaired DNA synthesis as a cataractogenic factor.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Case-Control Studies
  • Cataract / enzymology
  • Cataract / genetics*
  • DNA Mutational Analysis
  • Female
  • Gene Frequency
  • Genotype
  • Humans
  • Hyperhomocysteinemia / genetics
  • Male
  • Methylenetetrahydrofolate Reductase (NADPH2) / genetics*
  • Middle Aged
  • Polymorphism, Genetic*
  • Retrospective Studies
  • Sequence Analysis, DNA


  • Methylenetetrahydrofolate Reductase (NADPH2)