title: Combined factor VIII/factor XI deficiency may cause intra-familial clinical variability in haemophilia A among Ashkenazi Jews.
abstract: Heterozygous factor XI deficiency occurs very frequently among Ashkenazi Jews. To investigate the potential influence of a co-inherited factor XI deficiency state on the clinical phenotype of mild/moderate haemophilia A, 28 unrelated haemophiliacs of Jewish origin were screened for the two most common factor XI gene mutations. Gene lesions were identified in two out of 14 patients of Ashkenazi origin. In the one family analysed further, co-inheritance of both factor XI and factor VIII deficiencies was associated with a bleeding tendency that was more severe than that associated with either deficiency alone.
authors.affiliation: Charter Molecular Genetics Laboratory, Thrombosis Research Institute, London, UK.
authors.forename: L P
authors.initials: LP
authors.lastname: Berg
authors.forename: D
authors.initials: D
authors.lastname: Varon
authors.forename: U
authors.initials: U
authors.lastname: Martinowitz
authors.forename: K
authors.initials: K
authors.lastname: Wieland
authors.forename: V V
authors.initials: VV
authors.lastname: Kakkar
authors.forename: D N
authors.initials: DN
authors.lastname: Cooper
mesh_terms: D001483:Base Sequence; D015252:Deoxyribonucleases, Type II Site-Specific; D005173:Factor XI Deficiency / Q000150:complications*; D006467:Hemophilia A / Q000150:complications* / Q000235:genetics*; D007585:Jews; D008969:Molecular Sequence Data; D009154:Mutation; D010641:Phenotype; D016133:Polymerase Chain Reaction
chemical_list: C053864:endodeoxyribonuclease BsmI; D015252:Deoxyribonucleases, Type II Site-Specific; C024405:GATC-specific type II deoxyribonucleases