SMARCB1 and schwannomatosis: Second, the different pathologies caused by SMARCB1 mutations are strongly influenced by the type of the germline SMARCB1 pathogenic variant leading to either complete loss of SMARCB1 function in MRTs or a semi-functional SMARCB1 protein resulting from a pathogenic but hypomorphic SMARCB1 variant in patients with schwannomatosis.