NF2 is caused by mutations in the NF2 gene at chromosome 22q12.1, which encodes for a protein called merlin or schwannomin, most similar to the exrin-readixin-moesin (ERM) proteins; mosaicNF2 is due to mosaic phenomena for the NF2 gene, whilst schwannomatosis is caused by coupled germ-line and mosaic mutations either in the SMARCB1 gene [SWNTS1; MIM # 162091] or the LZTR1 gene [SWNTS2; MIM # 615670] both falling within the 22q region and the NF2 gene.
The ERM subgroup member merlin/schwannomin is inactivated in the tumor-predisposition syndrome neurofibromatosis 2 (NF2), and the prototypic 4.1 subgroup member, Protein 4.1B, has been implicated in the molecular pathogenesis of breast, lung and brain cancers.