Prevalence of sporadic and familial haemophilia.
In an analysis of 804 haemophilia pedigrees, mild to moderate haemophilia A or B was found to be clearly familial in 70% of cases, severe haemophilia B in 57% of cases and severe haemophilia A in 45% of cases. The rest of the patients were 'sporadic' i.e., either isolated cases or brothers in the first affected sibship. In sporadic families, 88% of mothers but only 19% of maternal grandmothers had the relevant mutation in their white blood cells. Among patients with familial haemophilia, half the patients with mild haemophilia and those with severe haemophilia B had a direct male ancestor with haemophilia, but only 28% of patients with severe haemophilia A had such a progenitor.
Kasper
C K
CK
Division of Hematology, Keck School of Medicine, University of Southern California, and Orthopaedic Hospital, Los Angeles, CA, USA. carolkasper@hotmail.com
Lin
J C
JC
D002140:California / Q000453:epidemiology; D002353:Carrier State; D005260:Female; D006467:Hemophilia A / Q000453:epidemiology* / Q000235:genetics; D002836:Hemophilia B / Q000453:epidemiology / Q000235:genetics; D006801:Humans; D008297:Male; D009030:Mosaicism; D009154:Mutation; D010375:Pedigree; D015995:Prevalence; D012189:Retrospective Studies