title: Intragenic Factor IX restriction site polymorphism in hemophilia B variants.
abstract: This study includes 47 normal subjects and 25 hemophilia B patients without inhibitor(s), showing different factor IX coagulant activity and antigen levels. Genomic DNA, digested with various restriction endonucleases, was hybridized with two different factor IX probes, ie, the cDNA and the subgenomic probe for the intragenic TaqI polymorphic site. cDNA restriction patterns suggest absence of gross rearrangements and/or deletions in all hemophilic patients. The frequency of the X chromosome bearing the TaqI polymorphic site is 0.32 +/- 0.09 in hemophilic subjects v 0.36 +/- 0.06 in normal control subjects, the latter value being comparable to that reported for the normal British population. No association between this polymorphism and hemophilia B variants has been observed, thus indicating that a wide spectrum of mutations underlies this blood-clotting disorder and particularly each of its variants.
authors.forename: H J
authors.initials: HJ
authors.lastname: Hassan
authors.forename: M
authors.initials: M
authors.lastname: Orlando
authors.forename: A
authors.initials: A
authors.lastname: Leonardi
authors.forename: C
authors.initials: C
authors.lastname: Chelucci
authors.forename: R
authors.initials: R
authors.lastname: Guerriero
authors.forename: P M
authors.initials: PM
authors.lastname: Mannucci
authors.forename: G
authors.initials: G
authors.lastname: Mariani
authors.forename: C
authors.initials: C
authors.lastname: Peschle
mesh_terms: D003001:Cloning, Molecular; D004262:DNA Restriction Enzymes / Q000235:genetics*; D015252:Deoxyribonucleases, Type II Site-Specific; D005164:Factor IX / Q000235:genetics* / Q000276:immunology; D005260:Female; D002836:Hemophilia B / Q000097:blood / Q000235:genetics* / Q000276:immunology; D006801:Humans; D007519:Isoantigens / Q000032:analysis; D008297:Male; D011110:Polymorphism, Genetic
chemical_list: D007519:Isoantigens; D005164:Factor IX; D004262:DNA Restriction Enzymes; D015252:Deoxyribonucleases, Type II Site-Specific; C027046:TCGA-specific type II deoxyribonucleases