FAT4 and neoplasm: Newly mutated genes identified in case 3B include FAT atypical cadherin 4 (FAT4), Importin 7 (IPO7), Cyclin K (CCNK), SH3 domain-binding kinase 1 (SBK1), and CD300A. Of these, FAT4, CCNK, and SBK1 have been previously linked to neoplasia [25–27] and may contribute to the aggressive behavior demonstrated by case 3.