These ZFN mutant rats were produced by injecting zinc finger nuclease targeting rat F8 into Sprague Dawley embryos. A premature translation stop in rat F8 was created in the mutant founders carrying a 13-bp deletion in exon 16. These mutant founders were backcrossed with Sprague Dawley to produce heterozygous offspring, which were then intercrossed to produce homozygous and heterozygous offspring.