Again the recent publication by Urreizti et al. shows that pathogenic gene variants are part in a reference database should be taken into account. In order to assess genetic variants, reference population databases such as the Exome Aggregation Consortium (ExAC) database are part of researches. It is assumed that in this population database pathogenic gene variants are absent or rare. Urreitzi et al. present a boy who has already been clinically diagnosed with Bohring-Opitz Syndrome (BOS). Sanger sequencing of ASXL1 revealed the p.Gly646Trpfs*12 mutation, an ASXL1 variant that is considered as causing Bohring-Opitz Syndrome. This variant is present in 132 persons from the reference database ExAC. Even though Carlston et al. 2017 discovered that in the ExAC database are BOS causing ASXL1 variants in individuals who are healthy with the conclusion that somatic mosaic of ASXL1 variants should be taken into account.
» Urreizti R, Gürsoy S, Castilla‐Vallmanya L, et al. The ASXL1 mutation p.Gly646Trpfs*12 found in a Turkish boy with Bohring‐Opitz Syndrome. Clin Case Rep. 2018;00:1–5. https://doi.org/10.1002/ccr3.1603
» Carlston CM, O’Donnell‐Luria AH, Underhill HR, et al. Pathogenic ASXL1 somatic variants in reference databases complicate germline variant interpretation for Bohring‐Opitz Syndrome. Human Mutation. 2017;38:517–523. https://doi.org/10.1002/humu.23203