NF2-, LZTR1– and SMARCB1-related schwannomatosis share significant clinical overlap. NF2-related schwannomatosis (NF2) is the commonest, but the form of schwannomatosis in people not meeting NF2 criteria is unclear.

We summarise genetic findings in paired germline and schwannoma DNA from people with schwannomas, but not meeting NF2 criteria. We show similar proportions of LZTR1, SMARCB1, or mosaic NF2 variants. We also found a high proportion with no identified germline variant, or an LZTR1 variant of uncertain significance, or with only one tumour who may still have mosaic NF2. Our results highlight the importance of comprehensive clinical genetic testing and variant classification. (By Dr Miriam J Smith, https://jmg.bmj.com/content/early/2024/08/29/jmg-2024-110217)