{"type":"root","children":[{"type":"paragraph","children":[{"type":"text","value":"The INI-1 gene, which encodes a functionally uncharacterized protein component of the hSWI/SNF chromatin remodeling complex, is involved in chromatin remodeling and transcriptional regulation and also known as hSNF5, SMARCB1 and BAF47."}]},{"type":"paragraph","children":[{"type":"text","value":"INI-1 is often mutated or deleted in malignant rhabdoid tumor (MRT). Two isoforms of INI-1, that differ by the variable inclusion of amino acids, potentially are produced by differential RNA splicing. The morphology of MRTs can present challenges in differential diagnosis. The overall survival of MRTs relative to its potential mimics such as medulloblastoma and supratentorial primitive neuroectodermal tumors (sPNETs) is quite low, and thus differentiation from these other tumors is desirable. Lack of nuclear labeling by INI-1 is characteristic of MRT. The majority of medulloblastomas and sPNETs are labeled by INI-1. MRTs also originate from the kidney and soft tissues. Germline INI-1 mutations are associated with sporadic schwannomatosis and rhabdoid tumors.\n INI-1 has been used to distinguish atypical teratoid / rhabdoid tumor (loss of INI1) from choroid plexus carcinoma (positive for INI-1) and to differentiate epithelioid sarcoma (loss of INI1) from epithelioid hemangioendothelioma (positive for INI-1)"}]}]}