title: Genetic and non-genetic factors that increase the risk of non-syndromic cleft lip and/or palate development.
abstract: OBJECTIVE
  We investigated the relationship between non-syndromic cleft lip/palate (NSCLP) and polymorphisms in methylenetetrahydrofolate reductase (MTHFR), methionine synthase (MTR), methionine synthase reductase (MTRR), and RFC1, as well as the corresponding interactions with environmental factors.
  
  
  METHODS
  One hundred and forty NSCLP patients and their mothers, as well as 175 control individuals and their mothers, were recruited. Information regarding smoking and alcohol consumption was recorded. Blood samples were obtained in order to measure serum folate and cobalamin, as well as, plasma total homocysteine concentrations and to extract DNA. Polymorphisms in MTHFR(677C>T and 1298A>C), MTR(2756A>G), MTR(66A>G), and RFC1(80A>G) were analyzed by PCR-restriction fragment length polymorphism.
  
  
  RESULTS
  Among the patients, 59.5% had cleft lip and palate, 22.0% had cleft palate, and 18.5% had cleft lip only. Maternal alcohol consumption and reduced folic acid concentrations in both children and mothers (P < 0.001 and P = 0.003, respectively) were risk factors for NSCLP. Patients and their mothers carrying the MTHFR 667T allele showed lower serum folate than CC (P = 0.011 and P = 0.030, respectively). Mothers who carried the MTHFR 1298C allele exhibited increased risk of having a child with NSCLP, after adjusting for alcohol consumption (OR: 1.75, 95% CI: 1.03-2.99, P = 0.038).
  
  
  CONCLUSIONS
  Reduced folic acid levels, alcohol consumption, and the MTHFR 677T and 1298C alleles may have contributed to NSCLP development in this sample population from Rio Grande do Norte.
authors.affiliation: Department of Clinical and Toxicological Analysis, Federal University of Rio Grande do Norte, Natal, RN, Brazil.
authors.forename: J F
authors.initials: JF
authors.lastname: Bezerra
authors.forename: G H M
authors.initials: GH
authors.lastname: Oliveira
authors.forename: C D
authors.initials: CD
authors.lastname: Soares
authors.forename: M L
authors.initials: ML
authors.lastname: Cardoso
authors.forename: M A G
authors.initials: MA
authors.lastname: Ururahy
authors.forename: F P F
authors.initials: FP
authors.lastname: Neto
authors.forename: L G
authors.initials: LG
authors.lastname: Lima-Neto
authors.forename: A D
authors.initials: AD
authors.lastname: Luchessi
authors.forename: V N
authors.initials: VN
authors.lastname: Silbiger
authors.forename: C M
authors.initials: CM
authors.lastname: Fajardo
authors.forename: S R de
authors.initials: SR
authors.lastname: Oliveira
authors.forename: M das G
authors.initials: Md
authors.lastname: Almeida
authors.forename: R D C
authors.initials: RD
authors.lastname: Hirata
authors.forename: A A de
authors.initials: AA
authors.lastname: Rezende
authors.forename: M H
authors.initials: MH
authors.lastname: Hirata
mesh_terms: D013766:5-Methyltetrahydrofolate-Homocysteine S-Methyltransferase / Q000235:genetics; D000293:Adolescent; D000328:Adult; D000428:Alcohol Drinking; D001921:Brain / Q000002:abnormalities*; D016022:Case-Control Studies; D002648:Child; D002971:Cleft Lip / Q000235:genetics*; D002972:Cleft Palate / Q000235:genetics*; D005260:Female; D005287:Ferredoxin-NADP Reductase / Q000235:genetics; D005492:Folic Acid / Q000097:blood; D059647:Gene-Environment Interaction; D006710:Homocysteine / Q000097:blood; D006801:Humans; D008297:Male; D042965:Methylenetetrahydrofolate Reductase (NADPH2) / Q000235:genetics*; D011110:Polymorphism, Genetic; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects / Q000235:genetics*; D051818:Replication Protein C / Q000235:genetics; D055815:Young Adult
chemical_list: C081632:RFC1 protein, human; D006710:Homocysteine; D005492:Folic Acid; C111241:methionine synthase reductase; D005287:Ferredoxin-NADP Reductase; C573423:MTHFR protein, human; D042965:Methylenetetrahydrofolate Reductase (NADPH2); D013766:5-Methyltetrahydrofolate-Homocysteine S-Methyltransferase; C585801:MTR protein, human; D051818:Replication Protein C
keywords: alcohol consumption; cleft lip and/or palate; folic acid; gene polymorphisms