677 C-->T polymorphism of the methylenetetrahydrofolate reductase gene and preeclampsia.
OBJECTIVE
To evaluate C to T substitution at nucleotide 677 of N(5), N(10)-methylenetetrahydrofolate reductase gene in women with prior preeclamptic or normotensive pregnancies.


METHODS
Methylenetetrahydrofolate reductase genotypes were determined in 113 Finnish women with preeclamptic first pregnancies and 103 controls with one or more normotensive pregnancies, using polymerase chain reaction and restriction enzyme analysis. Preeclampsia was defined as severe in 100 women who fulfilled one or more of the subsequent criteria: systolic blood pressure (BP) at least 160 mmHg, diastolic BP at least 110 mmHg, or proteinuria at least 2 g per 24-hour urine collection.


RESULTS
There were no significant differences in prevalences of the methylenetetrahydrofolate reductase genotypes (CC, CT, and TT) between groups (57%, 40%, and 3% in the preeclamptic group and 54%, 39%, and 7%, respectively, in controls). The frequency of the T677 allele was 0.23 in the preeclamptic group and 0.26 in the control group (difference 0.03; 95% confidence interval -0.08, 0.14; P =.51). Our sample had 60% power to detect a difference of the allele frequencies similar to that (0.12) reported previously. The result was similar when analysis was restricted to patients with severe preeclampsia (T677 allele frequency 0.22).


CONCLUSIONS
A carrier status for the T677 allele of the methylenetetrahydrofolate reductase gene does not predispose to preeclampsia, at least in the Finnish population.
Laivuori
H
H
Department of Obstetrics and Gynecology, Helsinki University Central Hospital, Helsinki, Finland. hannele.laivuori@pp.fimnet.fi
Kaaja
R
R
Ylikorkala
O
O
Hiltunen
T
T
Kontula
K
K
D000328:Adult; D000483:Alleles; D019943:Amino Acid Substitution; D016022:Case-Control Studies; D017931:DNA Primers; D005260:Female; D005387:Finland; D015971:Gene Expression Regulation, Enzymologic; D005787:Gene Frequency; D005838:Genotype; D006579:Heterozygote; D006801:Humans; D042965:Methylenetetrahydrofolate Reductase (NADPH2); D000587:Oxidoreductases Acting on CH-NH Group Donors / Q000235:genetics*; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D011225:Pre-Eclampsia / Q000201:enzymology / Q000235:genetics*; D011247:Pregnancy
D017931:DNA Primers; D000587:Oxidoreductases Acting on CH-NH Group Donors; D042965:Methylenetetrahydrofolate Reductase (NADPH2)