2). Cellular FLIPs are encoded by a single gene; in humans there are three main splice variants, long isoform (cFLIPL; 55 kDa), short isoform (cFLIPS; 26 kDa), and cFLIP Raji (cFLIPR; 24 kDa) first detected in the human Burkitt lymphoma B cell line Raji (3). Mice do not express cFLIPS and contain only two isoforms cFLIPL and cFLIPR (4). Here, CFLAR is linked to Burkitt lymphoma.