title: Identification and Genetic Analysis of a Factor IX Gene Intron 3 Mutation in a Hemophilia B Pedigree in China.
abstract: OBJECTIVE
  Hemophilia B is caused by coagulation defects in the factor IX gene located in Xq27.1 on the X chromosome. A wide range of mutations, showing extensive molecular heterogeneity, have been described in hemophilia B patients. Our study was aimed at genetic analysis and prenatal diagnosis of hemophilia B in order to further elucidate the pathogenesis of the hemophilia B pedigree in China.
  
  
  METHODS
  Polymerase chain reaction amplification and direct sequencing of all the coding regions was conducted in hemophilia B patients and carriers. Prenatal diagnosis of the proband was conducted at 20 weeks.
  
  
  RESULTS
  We identified the novel point mutation 10.389 A>G, located upstream of the intron 3 acceptor site in hemophilia B patients. The fetus of the proband's cousin was identified as a carrier.
  
  
  CONCLUSIONS
  Our identification of a novel mutation in the F9 gene associated with hemophilia B provides novel insight into the pathogenesis of this genetically inherited disorder and also represents the basis of prenatal diagnosis.
authors.affiliation: China Medical University, Department of Medical Genetics, Shenyang, China. E-ma-il: chunlianjin@126.com.
authors.forename: Dong-Hua
authors.initials: DH
authors.lastname: Cao
authors.forename: Xiao-Li
authors.initials: XL
authors.lastname: Liu
authors.forename: Kai
authors.initials: K
authors.lastname: Mu
authors.forename: Xiang-Wei
authors.initials: XW
authors.lastname: Ma
authors.forename: Jing-Li
authors.initials: JL
authors.lastname: Sun
authors.forename: Xiao-Zhong
authors.initials: XZ
authors.lastname: Bai
authors.forename: Chang-Kun
authors.initials: CK
authors.lastname: Lin
authors.forename: Chun-Lian
authors.initials: CL
authors.lastname: Jin