title: [Introns 1 and 22 inversions and F8 gene sequencing for molecular diagnosis of hemophilia A in Chile].
abstract: BACKGROUND
  Hemophilia A is an inherited disorder caused by alterations in factor VIII gene (F8) located on the X-chromosome, the intron 22 inversion being the most common mutation. The rest are predominantly point mutations distributed along this large gene of 26 exons.
  
  
  OBJECTIVE
  To implement a molecular diagnostic test to detect mutations in the F8 gene in Chilean patients with Hemophilia A.
  
  
  METHODS
  To validate the testing methods, we analyzed samples with intron 22 and intron 1 inversion, and with point mutations previously studied, as well as one subject without Hemophilia. We also studied unrelated Chilean patients with Hemophilia A and their female relatives for carrier testing. Intron 22 and intron 1 inversions were studied by long distance polymerase chain reaction (PCR) and point mutations by sequencing the coding and promoter regions of the F8 gene.
  
  
  RESULTS
  The results obtained in all samples used for validation were concordant with those obtained previously. In the Chilean patients, the intron 22 inversion and point mutations previously described were observed. In 6 out of 9 patients with mild Hemophilia A we found the same mutation (Arg2159Cys) in exon 23, which has been described as prevalent in mild Hemophilia A.
  
  
  CONCLUSIONS
  The analysis of intron 22 and intron 1 inversions, as well as of point mutations in the F8 gene will help us to confirm the diagnosis in patients with severe, moderate and mild Hemophilia A, and also it will allow us to perform carrier testing and to provide better genetic counseling.
authors.affiliation: Laboratorio de Biología Molecular, Departamento de Laboratorios Clínicos, Chile. hpoggi@med.puc.cl
authors.forename: Helena
authors.initials: H
authors.lastname: Poggi
authors.forename: Josefina
authors.initials: J
authors.lastname: Honorato
authors.forename: Eliana
authors.initials: E
authors.lastname: Romeo
authors.forename: Pamela
authors.initials: P
authors.lastname: Zúñiga
authors.forename: Teresa
authors.initials: T
authors.lastname: Quiroga
authors.forename: Marcela
authors.initials: M
authors.lastname: Lagos
mesh_terms: D007446:Chromosome Inversion; D005169:Factor VIII / Q000235:genetics*; D005260:Female; D006580:Genetic Carrier Screening / Q000379:methods; D006467:Hemophilia A / Q000175:diagnosis* / Q000235:genetics; D006801:Humans; D007438:Introns / Q000235:genetics*; D008297:Male; D017354:Point Mutation / Q000235:genetics; D016133:Polymerase Chain Reaction / Q000379:methods
chemical_list: D005169:Factor VIII