LZTR1 and schwannomatosis: So far, two schwannomatosis predisposition genes have been identified, SMARCB1 and LZTR1 (Hulsebos et al. 2007; Sestini et al. 2008; Hadfield et al. 2008; Smith et al. 2012b; Hutter et al. 2014; Piotrowski et al. 2014; Smith et al. 2015).