Methylenetetrahydrofolate reductase genetic polymorphisms in patients with cataract.
OBJECTIVE
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.


METHODS
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.
Zetterberg
Madeleine
M
Institute of Clinical Neuroscience, Section of Ophthalmology, Sahlgrenska University Hospital, Göteborg University, Mölndal, Sweden. madeleine.zetterberg@anatcell.gu.se
Tasa
Gunnar
G
Prince
Jonathan A
JA
Palmér
Mona
M
Juronen
Erkki
E
Veromann
Siiri
S
Teesalu
Pait
P
Karlsson
Jan-Olof
JO
Blennow
Kaj
K
Zetterberg
Henrik
H
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D002386:Cataract / Q000201:enzymology / Q000235:genetics*; D004252:DNA Mutational Analysis; D005260:Female; D005787:Gene Frequency; D005838:Genotype; D006801:Humans; D020138:Hyperhomocysteinemia / Q000235:genetics; D008297:Male; D042965:Methylenetetrahydrofolate Reductase (NADPH2) / Q000235:genetics*; D008875:Middle Aged; D011110:Polymorphism, Genetic; D012189:Retrospective Studies; D017422:Sequence Analysis, DNA
D042965:Methylenetetrahydrofolate Reductase (NADPH2)