TBX1 and cancer: Genomic sequencing of chordoma tumors has demonstrated that chordoma is a genomically quiet cancer: recurrent somatic events include amplifications of TBXT (encoding brachyury); homozygous deletion of CDKN2A; and mutations in PI3K signaling genes, SWI/SNF complex genes, and LYST; but nearly half of all sporadic chordoma cases do not harbor any known driver mutation15,16.