title: Endothelial nitric oxide synthase gene polymorphism in women with idiopathic recurrent miscarriage.
abstract: BACKGROUND
  Lack of endothelium-derived nitric oxide is associated with vasospasm and vascular infarction. We investigated the relationship between idiopathic recurrent miscarriage and a polymorphism of the gene encoding endothelial nitric oxide synthase (NOS3).
  
  
  METHODS
  In a prospective case-control study, 105 women with idiopathic recurrent miscarriage and 91 healthy controls were investigated. We used the polymerase chain reaction to identify the different alleles of a 27 base pair tandem repeat polymorphism in intron 4 of the NOS3 gene.
  
  
  RESULTS
  The wild type B allele was identified on 329 out of 392 chromosomes (frequency 0.84). The polymorphic A allele was present on 63 chromosomes (frequency 0.16). The genotype frequencies were as follows: 68% (B/B), 31% (A/B) and.5% (A/A). The distribution of genotype frequencies was significantly different between the study and control groups for allele A/B heterozygotes (NOS3(A/B)) (36.7 versus 23.8%, P = 0.03, OR 1.6, 95% CI 1.1--3.8). Only one individual was homozygous for the A allele (NOS3(A/A)). She was in the study group. Between women with primary and secondary recurrent miscarriages, no statistically significant difference between the distribution of NOS3(A/B) genotypes (28 versus 34%) was observed.
  
  
  CONCLUSIONS
  These data support a role for the NOS3 gene as a genetic determinant of the risk of idiopathic recurrent miscarriage.
authors.affiliation: Department of Gynaecology and Obstetrics, University of Vienna School of Medicine, Waehringer Guertel 18-20, A-1090 Vienna, Austria.
authors.forename: C
authors.initials: C
authors.lastname: Tempfer
authors.forename: G
authors.initials: G
authors.lastname: Unfried
authors.forename: R
authors.initials: R
authors.lastname: Zeillinger
authors.forename: L
authors.initials: L
authors.lastname: Hefler
authors.forename: F
authors.initials: F
authors.lastname: Nagele
authors.forename: J C
authors.initials: JC
authors.lastname: Huber
mesh_terms: D000026:Abortion, Habitual / Q000235:genetics*; D000328:Adult; D000483:Alleles; D016022:Case-Control Studies; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006579:Heterozygote; D006720:Homozygote; D006801:Humans; D019001:Nitric Oxide Synthase / Q000235:genetics*; D052250:Nitric Oxide Synthase Type III; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D011247:Pregnancy; D011446:Prospective Studies; D020080:Tandem Repeat Sequences
chemical_list: C496314:NOS3 protein, human; D019001:Nitric Oxide Synthase; D052250:Nitric Oxide Synthase Type III