title: [Detection and genetic counseling of F8 gene inversions for patients with severe hemophilia A].
abstract: OBJECTIVE
  Inversions of intron 1 (Inv1) or intron 22 (Inv22) of the coagulation factor VIII gene (F8) may be found in 40%-50% of patients with severe hemophilia A. Such inversions cannot be detected by conventional sequencing. Due to homologous recombination, family-based linkage analysis may yield false positive or false negative results. In this study, Inverse-shifting PCR (IS-PCR) was used to detect potential inversions in two families affected with hemophilia A.
  
  
  METHODS
  Peripheral venous blood, fetal amniotic fluid and fetal chorionic cells were harvested for genome DNA extraction. IS-PCR was used to detect Inv1 or Inv22 detection or its subtypes.
  
  
  RESULTS
  IS-PCR has accurately detected Inv22 and Inv1 in both families and verified the subtypes of Inv22.
  
  
  CONCLUSIONS
  Carriers of Inv22 or Inv1 may be precisely detected with IS-PCR. The results have provided valuable information for genetic counseling and prenatal diagnosis for the affected families.
authors.affiliation: Prenatal Diagnosis Center, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052, China. Email: kongxd@263.net.
authors.forename: Nan
authors.initials: N
authors.lastname: Bai
authors.forename: Qinghua
authors.initials: Q
authors.lastname: Wu
authors.forename: Ning
authors.initials: N
authors.lastname: Liu
authors.forename: Duo
authors.initials: D
authors.lastname: Chen
authors.forename: Zhenhua
authors.initials: Z
authors.lastname: Zhao
authors.forename: Xiangdong
authors.initials: X
authors.lastname: Kong
mesh_terms: D002648:Child; D007446:Chromosome Inversion; D005169:Factor VIII / Q000235:genetics*; D005817:Genetic Counseling; D006467:Hemophilia A / Q000175:diagnosis / Q000235:genetics*; D006801:Humans; D007438:Introns; D008297:Male; D011296:Prenatal Diagnosis
chemical_list: D005169:Factor VIII