Genetic susceptibility to preeclampsia: roles of cytosineto-thymine substitution at nucleotide 677 of the gene for methylenetetrahydrofolate reductase, 68-base pair insertion at nucleotide 844 of the gene for cystathionine beta-synthase, and factor V Leiden mutation.
OBJECTIVE
The purpose of this study was to evaluate the association between preeclampsia and 3 relatively common mutations that are important in the development of vascular disease and thrombosis; these are similar to conditions observed in pregnancies complicated by preeclampsia.


METHODS
Deoxyribonucleic acid was extracted from whole blood or cheek swabs of 281 patients with preeclampsia and 360 control subjects (all white). Control subjects consisted of women who had undergone at least 2 term pregnancies unaffected by preeclampsia. Mutation frequencies among patients with preeclampsia and control subjects were compared by standard chi2 analysis, with P <.05 considered significant.


RESULTS
Thirty-three of 281 women with preeclampsia (11.7%) and 22 of 193 women with severe preeclampsia (11.4%) were homozygous for cytosine-to-thymine substitution at nucleotide 677 in the gene for methyltetrahydrofolate reductase (MTHFR), versus 41 of 360 control subjects (11.4%; difference not significant). Forty of 258 women with preeclampsia (15.5%) and 22 of 175 women with severe preeclampsia (12.6%) were heterozygous for the insertion of 68 bases at position 844 in the gene for cystathionine beta-synthase (CBS), versus 58 of 332 control subjects (17.5%). Fifteen of 250 women with preeclampsia (6.0%) and 11 of 169 with severe preeclampsia (6.5%) were heterozygous for the Leiden mutation (glycine-to-alanine substitution at nucleotide 1691) in the gene for factor V (F5), versus 12 of 253 control subjects (4.7%; difference not significant).


CONCLUSIONS
In this white population a missense mutation of MTHFR, an insertion mutation of CBS, and a missense mutation of F5 were not found to be associated with an increased risk for preeclampsia, either independently or in combination.
Kim
Y J
YJ
Department of Obstetrics and Gynecology, University of Iowa, Iowa City, USA.
Williamson
R A
RA
Murray
J C
JC
Andrews
J
J
Pietscher
J J
JJ
Peraud
P J
PJ
Merrill
D C
DC
D019943:Amino Acid Substitution; D003541:Cystathionine beta-Synthase / Q000235:genetics*; D004251:DNA Transposable Elements; D005165:Factor V / Q000235:genetics*; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D006579:Heterozygote; D006720:Homozygote; D006801:Humans; D042965:Methylenetetrahydrofolate Reductase (NADPH2); D020125:Mutation, Missense / Q000502:physiology*; D000587:Oxidoreductases Acting on CH-NH Group Donors / Q000235:genetics*; D011225:Pre-Eclampsia / Q000235:genetics*; D011247:Pregnancy
D004251:DNA Transposable Elements; C095381:factor V Leiden; D005165:Factor V; D000587:Oxidoreductases Acting on CH-NH Group Donors; D042965:Methylenetetrahydrofolate Reductase (NADPH2); D003541:Cystathionine beta-Synthase