title: Polymorphisms of the Nos3 gene and unexplained late intrauterine fetal death.
abstract: OBJECTIVE
  Genetic polymorphisms associated with vascular diseases have been proposed to be involved in the pathogenesis of late unexplained intrauterine fetal death (IUFD). The Nos3 gene is known to regulate vascular tone via the endothelial nitric oxide synthase/nitric oxide pathway.
  
  
  METHODS
  In a multicenter case-control study, we evaluated two Nos3 polymorphisms (exon 7 Glu298Asp and a 27bp-repeat in intron 4) in 92 women with IUFD and 92 healthy control women.
  
  
  RESULTS
  The investigated Nos3 polymorphisms were not associated with the occurrence of IUFD. In the subgroup of pregnancies affected by IUFD, women with at least one mutant allele of the Nos3 intron 4 polymorphism were diagnosed with IUFD at a significantly earlier gestational age (31.8 [standard deviation (S.D.) = 4.9] weeks versus 34.6 [S.D. = 4.8] weeks, p = 0.02) and showed a significantly reduced birth weight (2113 g [S.D. = 1028] versus 1571 g [S.D. = 568], p = 0.03).
  
  
  CONCLUSIONS
  We are the first to report on Nos3 polymorphisms and IUFD. While not being associated with the incidence of IUFD overall, the intron 4 Nos3 polymorphism might modulate the timing of IUFD in affected pregnancies.
authors.affiliation: Department of Obstetrics and Gynecology, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna, Austria.
authors.forename: Ambros
authors.initials: A
authors.lastname: Huber
authors.forename: Christoph
authors.initials: C
authors.lastname: Grimm
authors.forename: Stefan
authors.initials: S
authors.lastname: Jirecek
authors.forename: Kurt
authors.initials: K
authors.lastname: Heim
authors.forename: Robert
authors.initials: R
authors.lastname: Zeillinger
authors.forename: Peter
authors.initials: P
authors.lastname: Husslein
authors.forename: Lukas
authors.initials: L
authors.lastname: Hefler
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D005260:Female; D005313:Fetal Death / Q000235:genetics*; D005838:Genotype; D006801:Humans; D007438:Introns / Q000235:genetics; D008297:Male; D052250:Nitric Oxide Synthase Type III / Q000235:genetics*; D011110:Polymorphism, Genetic; D011247:Pregnancy; D011263:Pregnancy Trimester, Third; D044465:White People
chemical_list: C496314:NOS3 protein, human; D052250:Nitric Oxide Synthase Type III