title: Polymorphisms in genes RFC-1/CBS as maternal risk factors for Down syndrome in China.
abstract: OBJECTIVE
  To explore the relationship between genetic polymorphisms in reduced folate carrier 1 (RFC-1), cystathionine b-synthase (CBS), two key genes in folate metabolism, and the risk of Down syndrome in China.
  
  
  METHODS
  Genomic DNA was isolated from the peripheral lymphocytes of 104 mothers born children with Down syndrome and 184 age-matched control mothers. Polymerase chain reaction and restriction-fragment length polymorphism were used to examine the polymorphisms of RFC-1 A80G, CBS T833C and the relationship between these genotypes and the risk of Down syndrome was analyzed.
  
  
  RESULTS
  We found that there were significant differences between RFC-1 G80G, CBS C833C polymorphisms among mothers of children with Down syndrome than among control mothers, with odds ratio of 1.51 (95 % CI 1.05-2.18), 1.53 (95 % CI 1.07-2.18) respectively. The combined presence of RFC1 mutant alleles and the CBS homozygous mutant allele (15/104) was associated with a 4.81-fold increased risk of having a child with Down syndrome (95 % CI 1.82-12.68, P = 0.0007).
  
  
  CONCLUSIONS
  We concluded that RFC-1 and CBS gene mutation alleles are related to Down syndrome, and women with mutation RFC-1 G80G, CBS C833C OR combined with RFC-1 A80G and CBS 833TT genotype increase the risk of Down syndrome in China.
authors: Prenatal Eugenics Diagnosis Center of Department of Obstetrics and Gynecology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
authors: Shao-shuai
authors: SS
authors: Wang
authors: Chao
authors: C
authors: Wang
authors: Fu-yuan
authors: FY
authors: Qiao
authors: Juan-juan
authors: JJ
authors: Lv
authors: Ling
authors: L
authors: Feng
mesh_terms: D000328:Adult; D000483:Alleles; D044466:Asian People / Q000235:genetics*; D015415:Biomarkers; D016022:Case-Control Studies; D002681:China; D016001:Confidence Intervals; D003541:Cystathionine beta-Synthase / Q000235:genetics*; D004314:Down Syndrome / Q000235:genetics*; D005260:Female; D005492:Folic Acid / Q000378:metabolism; D005838:Genotype; D006801:Humans; D016017:Odds Ratio; D020641:Polymorphism, Single Nucleotide; D051818:Replication Protein C / Q000235:genetics*; D012307:Risk Factors; D055815:Young Adult
chemical_list: D015415:Biomarkers; C081632:RFC1 protein, human; D005492:Folic Acid; D051818:Replication Protein C; D003541:Cystathionine beta-Synthase