A large deletion due to a new mutation (intron 13/exon 23) in a sporadic case of severe hemophilia A

Clin Appl Thromb Hemost. 2004 Jan;10(1):61-4. doi: 10.1177/107602960401000110.


A case of sporadic hemophilia A in a young child was investigated from a molecular biology point of view. The propositus is a 4-year-old severe hemophiliac who was first seen when he was 2 years old. At that time, easy bruising and hematomas were noted because of accidental falls while toddling. The coagulation study showed a prolonged partial thromboplastin time and a factor VIII level of 1.3% of normal. Molecular biologic analysis showed a large deletion involving intron 13 up to exon 23. In the inversion study, the propositus exhibited only a 10 kb band, and this result suggests that intron 22 was deleted while his mother shows a normal pattern. To further examine the length of the deletion, a long polymerase chain reaction by means of primers amplifying the region from exon 13 to 23. In the index patient, an approximate 13-kb product was obtained, whereas no product was obtained from his mother. The mother investigated by means of polymorphism was shown not to be a carrier.

Publication types

  • Case Reports

MeSH terms

  • Child, Preschool
  • DNA Mutational Analysis
  • Exons
  • Family Health
  • Female
  • Hemophilia A / diagnosis
  • Hemophilia A / genetics*
  • Humans
  • Introns
  • Male
  • Mothers
  • Mutation*
  • Sequence Deletion*