It has been determined that most mutations in factor VIII occur in multiple haplotypes, not primarily in one haplotype. The frequencies of mild, moderate, and severe hemophilia did not differ significantly according to the background haplotype. The odds of having inhibitor were significantly higher among patients in the H3+H4 haplotype groups as compared to H1+H2 haplotype groups. This association appears to be independent of the mutation. The results indicate that white hemophiliacs should be treated with Kogenate®. However, it would clearly be of benefit to assess the haplotype of black hemophiliacs prior to prescribing the recombinant FVIII to be used for treatment. It is not essential to determine the actual mutations responsible for the hemophilia prior to prescribing the recombinant FVIII. Also described are transgenic human FVIII animal models.
