title: [Gene analysis in four inherited coagulation FⅫ deficiency pedigree].
abstract: OBJECTIVE
  To identify the genotype and pathogenesis in four Chinese pedigrees with Factor Ⅻ deficiency.
  
  
  METHODS
  Activated partial thromboplastin time (APTT), FⅫ procoagulant activity (FⅫ∶C), FⅫ antigen（FⅫ∶Ag）and other coagulant parameters were detected. The FⅫ deficiency Pedigree members,all exons,boundary introns including the splice junctions of the FⅫ gene were amplified with Polymerase chain reaction (PCR). Expression plasmids were constructed by mutagenesis based on the wild-type and transfected into COS7 cells. FⅫ∶C and FⅫ∶Ag of the expression levels were tested in the supernatant and cell lysate.
  
  
  RESULTS
  The four probands presented prolonged APTT with all the values of FⅫ∶C and FⅫ∶Ag were low to 2% and 1%, respectively. There were common 46C/T polymorphism in the promoter regions of FⅫ gene in four pedigrees. Proband A was heterozygous for two mutations, g.5741-5742delCA (His101Gln) and g.7142insertC (Lys346Gln). Proband B was a heterozygous deletion mutation g.6800-6808del9bp. The results of the transfection revealed that FⅫ∶Ag in cell lysates and conditioned media protein FⅫ6800-6808del9bp were 85.6% and 51.9%. The FⅫ∶C in the conditioned media was 56.4%. Proband C was a heterozygous mutation g.8699G>A(Gly542Ser). Proband D was a homozygous mutation 8699G>A, whose parents with consanguineous marriage.
  
  
  CONCLUSIONS
  Four mutations, g.5741-5742delCA, g.7142insertC, g.6800-6808del9bp and g.8699G>A with 46C/T polymorphism in the promoter regions of FⅫ gene, were identified in the four Factor Ⅻ deficiency pedigrees. The two mutations g.5741-5742delCA and g.6800-6808del9bp were first found in China. FⅫ 6800-6808del9bp expressed in vitro suggested that almost normal proteinum synthesis but defect proteinum secretion.
authors.affiliation: Diagnosis Center of Clinical Laboratory, the First Hospital Affiliated of Wenzhou Medical College,Wenzhou,China.
authors.forename: Hai-xiao
authors.initials: HX
authors.lastname: Xie
authors.forename: Mei-yan
authors.initials: MY
authors.lastname: Lv
authors.forename: Xiao-li
authors.initials: XL
authors.lastname: Yang
authors.forename: Ming-shan
authors.initials: MS
authors.lastname: Wang
authors.forename: Yang
authors.initials: Y
authors.lastname: Zhang
authors.forename: Li-qing
authors.initials: LQ
authors.lastname: Zhu
authors.forename: Yan-hui
authors.initials: YH
authors.lastname: Jin
authors.forename: Li-hong
authors.initials: LH
authors.lastname: Yang
mesh_terms: D000328:Adult; D000368:Aged; D004252:DNA Mutational Analysis; D005174:Factor XII / Q000235:genetics*; D005175:Factor XII Deficiency / Q000235:genetics*; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D009154:Mutation; D010375:Pedigree; D011110:Polymorphism, Genetic
chemical_list: D005174:Factor XII