A large deletion due to a new mutation (intron 13/exon 23) in a sporadic case of severe hemophilia A.
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.
Department of Medical and Surgical Sciences, 2nd Chair of Internal Medicine, University of Padua Medical School, Padua, Italy. annamaria.lombardi@unipd.it
Anna Maria
AM
Lombardi
Laura
L
Cabrio
Ezio
E
Zanon
Maria Teresa
MT
Sartori
Filippo
F
Navaglia
Mario
M
Plebani
Antonio
A
Girolami
D002675:Child, Preschool; D004252:DNA Mutational Analysis; D005091:Exons; D005192:Family Health; D005260:Female; D006467:Hemophilia A / Q000175:diagnosis / Q000235:genetics*; D006801:Humans; D007438:Introns; D008297:Male; D009035:Mothers; D009154:Mutation; D017384:Sequence Deletion