title: Characterization of heterogeneity of haemophilia B for the detection of carriers.
abstract: Factor IX activity (IX:C) and antigern (IX:Ag) as well as factor VII, prothrombin time, Normotest and Thrombotest were determined in 37 haemophiliacs B from 26 kindreds, in 30 carriers of haemophilia B and in 40 healthy subjects. In 15 obligatory carriers from 9 kindreds, in which haemophiliacs did not exhibit IX:Ag in excess of IX:C, IX:C was parallel with IX:Ag, but in 4 from 4 kindreds, in which haemophiliacs exhibit excess of IX:Ag, there was a discrepancy between IX:C and IX:Ag. Among the obligatory carriers 6 from 3 kindreds, in which haemophiliacs did not have IX:Ag in excess of IX:C, showed that the anomaly M is not a sign of genetic variability of haemophilia B.
mesh_terms: D000939:Epitopes; D005164:Factor IX / Q000276:immunology* / Q000502:physiology; D005260:Female; D006580:Genetic Carrier Screening / Q000379:methods*; D014644:Genetic Variation; D002836:Hemophilia B / Q000235:genetics* / Q000276:immunology; D006801:Humans; D007122:Immunoelectrophoresis; D008297:Male; D010314:Partial Thromboplastin Time
chemical_list: D000939:Epitopes; D005164:Factor IX