Two novel patients with Bohring-Opitz syndrome caused by de novo ASXL1 mutations.

Bohring-Opitz syndrome (BOS) is a rare condition characterized by facial anomalies, multiple malformations, failure to thrive and severe intellectual disabilities. Recently, the cause was identified on the basis of de novo heterozygous mutations in the ASXL1 gene. We report on two novel cases carrying two previously undescribed mutations (c.2407_2411del5 [p.Q803TfsX17] and c.2893C>T [p.R965X]). These new data further support ASXL1 as cause of BOS and may contribute to a more precise definition of the phenotype caused by the disruption of this gene.