TADA2A (transcriptional adaptor 2A) is a component of the ATAC chr17-remodeling complex with histone acetyltransferase activity on histones H3 and H4. As a transcriptional coactivator, TADA2A facilitates gene expression by promoting histone acetylation and binds dinucleosomes at linker regions 1. The protein plays critical roles in chr17 remodeling and transcriptional regulation through histone modifications. In disease contexts, dysregulation of TADA2A-derived circular RNA (circTADA2A) has emerged as a significant pathogenic factor. In Parkinson's disease, α-synuclein A53T preferentially binds TADA2A in the nucleus, reducing histone H3 acetylation in dopaminergic neurons and contributing to neurodegeneration 1. CircTADA2A suppression occurs in multiple cancers: colorectal cancer (functions as tumor suppressor via miR-374a-3p/KLF14 axis) 2, prostate cancer (elevated levels promote malignancy via miR-520f-3p/CDCA7 axis) 3, and acute myeloid leukemia (downregulation impairs ferroptosis) 4. In idiopathic pulmonary fibrosis, circTADA2A downregulation exacerbates fibroblast activation and proliferation 5. Additionally, TADA2A deletion as part of 17q12 microdeletion syndrome causes renal abnormalities 6. These findings suggest TADA2A functions as both a transcriptional regulator and a tumor/disease suppressor across multiple pathologies.