LZTR1 and schwannomatosis: Schwannomatosis is caused by heterozygous germline pathogenic variants in known predisposing genes SMARCB1 (MIM# 601607) or LZTR1 (MIM# 600574) located on chromosome 22q11.2 (Hulsebos et al., 2007; Piotrowski et al., 2014), but other predisposing genes are likely in view of the absence of a germline variant to account for at least 14%–30% of even familial cases.