title: Maternal polymorphisms for methyltetrahydrofolate reductase and methionine synthetase reductase and risk of children with Down syndrome.
abstract: OBJECTIVE
  The purpose of this research was to study factors that are involved in centromeric hypomethylation in the pathogenesis of Down syndrome (DS).
  
  
  METHODS
  This was a case-control study to evaluate the association between methyltetrahydrofolate reductase (MTHFR) C677T and methionine synthetase-reductase (MTRR) A66G polymorphisms and the risk of DS; we compared mothers in Italy who had children with DS and matched control subjects.
  
  
  RESULTS
  Seventy-four cases of DS caused by an error in maternal meiosis were compared with 184 matched control subjects. The frequencies of the MTHFR C677T polymorphism were similar between the 2 groups. As regards the MTRR A66G polymorphism, the presence of the mutated G allele either in the heterozygous or homozygous form was significantly more common among mothers of children with DS than among control subjects (odds ratio, 2.21; 95% CI, 1.11-4.40).
  
  
  CONCLUSIONS
  In a population with a high prevalence of the mutated T allele, maternal MTRR A66G, but not MTHFR, polymorphisms are associated with Down syndrome.
authors.affiliation: Department of Obstetrics and Gynecology, University of Milano-Bicocca, S. Gerardo Hospital, Monza, Italy. pozzi.elisa@tiscali.it
authors.forename: Elisa
authors.initials: E
authors.lastname: Pozzi
authors.forename: Patrizia
authors.initials: P
authors.lastname: Vergani
authors.forename: Leda
authors.initials: L
authors.lastname: Dalprà
authors.forename: Romina
authors.initials: R
authors.lastname: Combi
authors.forename: Daniela
authors.initials: D
authors.lastname: Silvestri
authors.forename: Francesca
authors.initials: F
authors.lastname: Crosti
authors.forename: Mariagrazia
authors.initials: M
authors.lastname: Dell'Orto
authors.forename: Maria Grazia
authors.initials: MG
authors.lastname: Valsecchi
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D002648:Child; D004314:Down Syndrome / Q000235:genetics*; D005260:Female; D005287:Ferredoxin-NADP Reductase / Q000235:genetics*; D006801:Humans; D042965:Methylenetetrahydrofolate Reductase (NADPH2) / Q000235:genetics*; D009035:Mothers; D011110:Polymorphism, Genetic; D012307:Risk Factors; D055815:Young Adult
chemical_list: C111241:methionine synthase reductase; D005287:Ferredoxin-NADP Reductase; D042965:Methylenetetrahydrofolate Reductase (NADPH2)