In hemophilia A and B, analysis of the F8 and F9 variants has become
standard over recent decades, giving information on the severity of
hemophilia, inhibitor formation and allowing counseling for the
families. The PedNet Registry collects data on hemophilia in children
and has more than 2000 children listed. Genetic reports are collected
uniformly and re-evaluated following international guidelines. We report
90 novel variants in the F8 and F9 gene, respectively, causing
hemophilia with detailed information on severity, factor level and
inhibitor formation. This will lead to further guidance for genetic
laboratories and the treating physician. These findings can be
implemented in hemophilia variant databases. The study highlights the
need to re-evaluate and update earlier genetic reports in hemophilia
both locally but also in variant databases in the light of changed
nomenclature, the use of in silico prediction and new sequencing
techniques.