title: [Analysis of an hereditary coagulation factor XII deficiency in a consanguineous pedigree].
abstract: OBJECTIVE
  To analyze genetic mutation and explore its molecular pathogenesis for an hereditary coagulation factor XII(F XII) deficiency in a pedigree featuring consanguineous marriage.
  
  
  METHODS
  Activated partial thromboplastin time (APTT), F XII procoagulant activity (F XII:C), F XII antigen (F XII:Ag) and other coagulant parameters were assayed. For the proband and his family members, exons 1-4, introns including the splice junctions of the F XII gene were amplified with polymerase chain reaction (PCR). The PCR product was purified and sequenced. The mutations were confirmed by sequencing the complimentary strand.
  
  
  RESULTS
  The proband has featured prolonged APTT at 157.5 s (reference range, 27.0-41.0 s). The APTT of his son has increased slightly at 48.3 s. The remaining members of the family were in normal range. F XII activity and F XII antigen of the proband were significantly decreased (<1%). The F XII activity of his wife, daughter, son and mother was also dropped to about 51%, 21%, 21% and 50%, respectively, and so was the F XII antigen (42%, 32%, 37% and 48%, respectively). Homozygous missense mutation of G→A transition at position 8699 in exon 14 resulting in Gly542Ser was identified in the proband. His mother, son and daughter were heterozygous for Gly542Ser. In the promoter regions of  F XII gene, the genotype of the proband and the other members was 46T/T.
  
  
  CONCLUSIONS
  Homozygous missense mutation Gly542Ser was found in a pedigree of hereditary F XII deficiency. The homozygous missense mutation might have resulted from his parents by consanguineous marriage. Gly542Ser and 46T/T have contributed to the pathogenesis of the hereditary factor XII deficiency pedigree.
authors.affiliation: Wenzhou Medical College, Wenzhou, Zhejiang, People's Republic of China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Zhang
authors.forename: Hai-xiao
authors.initials: HX
authors.lastname: Xie
authors.forename: Ming-shan
authors.initials: MS
authors.lastname: Wang
authors.forename: Yan-hui
authors.initials: YH
authors.lastname: Jin
authors.forename: Yao-sheng
authors.initials: YS
authors.lastname: Xie
authors.forename: Fang-xiu
authors.initials: FX
authors.lastname: Zheng
mesh_terms: D000328:Adult; D001483:Base Sequence; D001780:Blood Coagulation Tests; D003241:Consanguinity; D005091:Exons; D005174:Factor XII / Q000235:genetics; D005175:Factor XII Deficiency / Q000097:blood / Q000235:genetics*; D005260:Female; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D010375:Pedigree; D020641:Polymorphism, Single Nucleotide; D055815:Young Adult
chemical_list: D005174:Factor XII