Recurrent de novo pathogenic variant of WASF1 in a Japanese patient with neurodevelopmental disorder with absent language and variable seizures.

A recurrent de novo pathogenic variant of WASF1, NM_003931:c.1516C>T [p.Arg506*], was identified in a 6-year-old female Japanese patient with severe developmental delay, hypotonia, hyperkinetic behavior, and distinctive facial features. The initial report of five adult patients with WASF1 variants was the only previous report regarding variants of this gene; this is the second such report, reaffirming that rare but recurrent truncating variants of WASF1 are associated with severe neurodevelopmental disorders.