title: Identification of a single nucleotide C-to-T transition and five different deletions in patients with severe hemophilia B.
abstract: DNA of 70 unrelated hemophilia B patients, including three inhibitor patients, was analyzed by using various restriction enzymes and was hybridized with both a factor IX cDNA and 3'- and 5'-flanking probes. When the gene was mapped this way, six patients all afflicted with severe hemophilia B were shown to have a deviating hybridization pattern. One inhibitor patient showed a partial deletion of about 9 kb that removes exons a-c. A partial deletion of at least 11 kb that removed exon a and that had a maximum size of 35 kb in the 5'-flanking region could be identified in a patient of unknown status. In another three noninhibitor patients a complete deletion of the factor IX gene and two partial deletions could be observed. The partial deletions are of approximately 8 kb and approximately 1.5 kb, removing exons d and e and exon g, respectively. As detected by oligonucleotide probing, a C-to-T transition at amino acid 338 gave rise to an altered TaqI restriction pattern that could be observed in a sixth patient. The other 64 hemophilia B patients, including two inhibitor patients, showed a hybridization pattern indistinguishable from a normal one.
authors.affiliation: Institute of Experimental Haematology and Blood Transfusion, Bonn, Federal Republic of Germany.
authors.forename: M
authors.initials: M
authors.lastname: Ludwig
authors.forename: R
authors.initials: R
authors.lastname: Schwaab
authors.forename: A
authors.initials: A
authors.lastname: Eigel
authors.forename: J
authors.initials: J
authors.lastname: Horst
authors.forename: H
authors.initials: H
authors.lastname: Egli
authors.forename: H H
authors.initials: HH
authors.lastname: Brackmann
authors.forename: K
authors.initials: K
authors.lastname: Olek
mesh_terms: D002872:Chromosome Deletion; D003596:Cytosine; D004247:DNA / Q000097:blood / Q000235:genetics; D005164:Factor IX / Q000235:genetics; D005260:Female; D005796:Genes; D006467:Hemophilia A / Q000235:genetics*; D006801:Humans; D008297:Male; D009154:Mutation; D010375:Pedigree; D012016:Reference Values; D015183:Restriction Mapping; D013941:Thymine
chemical_list: D003596:Cytosine; D005164:Factor IX; D004247:DNA; D013941:Thymine