Non-canonical complexes (ncBAF) localize to the transcriptional repressor CTCF (also known as 11-zinc finger protein or CCCTC-binding factor) and can act as synthetic lethal targets specific for synovial sarcoma (SS) and malignant rhabdoid tumor (MRT) (16) or other cBAF-disrupted cancers. The gene discussed is CTCF; the disease is synovial sarcoma.