CDKN2B and schwannomatosis: The purpose of this study was to assess the contribution of variants in COQ6, DGCR8, CDKN2A, and CDKN2B to pathogenesis in a group of patients whose clinical features are consistent with schwannomatosis diagnosis, but for whom routine genetic analysis failed to identify PVs in the known schwannomatosis genes; NF2, SMARCB1, and LZTR1.