Abstract

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.