B6.129P2-F9^tm1Dws/J

Stock number: 004303
Research areas: Hematological Research

Description

These F9 knock-out mice exhibit curtailed clotting activity with spontaneous hemorrhage in footpad tissues and subcutaneous hemorrhages.

Detailed description

Mice that are homozygous for this targeted mutation are viable, fertile and normal in size. As this mutation is X-linked, males bearing the targeted allele display a mutant phenotype similar to that seen in homozygous females. Gene product activity, as measured by clotting activity using an activated partial thromboplastin time (APTT) Factor IX assay, was reduced to 8% of normal. Mutant mice experience spontaneous bleeding that can lead to swelling of the top of the feet or the footpads. Sudden death due to massive internal hemorrhaging can occur as a result of normal fighting in the cage. Tail cut wounds must be cauterized to prevent blood loss and death in mutant mice. This mutant mouse strain represents a model that may be useful in studies related to gene therapy methods and function of factor IX mutations.

Development

A targeting vector containing a neomycin resistance gene, herpes simplex virus thymidine kinase gene and a hypoxanthine phosphoribosyl transferase minigene (partially deleted and nonfunctional) was used to disrupt exons 1-3 of the targeted gene. The construct was electroporated into 129P2/OlaHsd derived E14TG2a embryonic stem (ES) cells. Correctly targeted ES cells were injected into C57BL/6 blastocysts. The resulting male chimeric animals were backcrossed to C57BL/6J mice for 10 generations.

Allele

Symbol: F9^tm1Dws
Name: targeted mutation 1, Darrel W Stafford
MGI accession ID: MGI:1932297
Generation method: Targeted
Attributes: Null/Knockout
Marker symbol: F9
Marker name: coagulation factor IX
Chromosome: X
Strain of origin: 129P2/OlaHsd
Molecular note: Exons 1, 2 and 3 are replaced by a neomycin/hprt minigene cassette. No mRNA was detected in hemizygous male mice as assayed by RT-PCR analysis.