Mice with hemophilia B have been engineered using gene targeting techniques. These animals exhibit severe factor IX deficiency and a clinical phenotype that mirrors the human disease. We have bred the founder animals onto two different strains of mice, C57B1/6 and CD-1, and have sought to determine whether adenoviral vectors expressing human factor IX could correct the bleeding diathesis of mic...

Factor IX has been expressed to high levels within a recombinant host cell and the biologically active fraction subsequently purified to homogeneity for characterization. The coding sequence for Factor IX was inserted into a mammalian cell expression vector and transfected into dihydrofolate reductase-deficient Chinese hamster ovary cells. The integrated DNA was amplified to a high copy number ...

Haemophilia B is caused by coagulation defects in the factor IX gene located in Xq27.1 on the X chromosome. Identification of mutations contributing to defective factor IX may be advantageous for precise carrier and prenatal diagnosis. We studied 16 patients from 11 families, consisting of 8 patients of the Malay ethnic group, of which 6 were siblings. Factor IX mutations have not been previous...

Background: Pilot and large-scale production of recombinant proteins requires the presence of stable clones capable of producing large quantities of recombinant proteins. Not only the process of selecting stable clones is time consuming, but also the continuous culturing of clones in large-scale production may cause loss of incoming plasmid and recombinant genes. Thus, considering the advanceme...

Hemophilia B Leyden is characterized by low levels of factor IX antigen and activity before the age of 15 years, whereas after puberty factor IX levels rise at a rate of about 5% per year. Two distinct point mutations (deletion of A, A----G) were identified at position +13 of the factor IX gene of a Greek and an American patient with hemophilia B Leyden. The nucleotide changes have occurred 32 ...

Hemophilia B is a leading target for gene therapy because current therapy is not optimal. Hence, a murine model of factor IX (F. IX) deficiency was generated to develop gene therapy strategies for hemophilia B. A targeting vector was created by replacing a 3.2-kb segment of the gene encompassing the catalytic domain with a phosphoglycerokinase promoter-driven neomycin resistant (neor) gene cass...

DNA from 20 Italian haemophilia B patients was analysed by the Southern blotting technique and hybridisation to a factor IX cDNA probe. A large deletion of factor IX gene was detected in one patient with antibodies to the infused factor; the EcoRI pattern of the other 19 subjects examined was normal.