TAL1 and acute lymphoblastic leukemia: TAL1 is commonly deregulated in human T-ALL and is co-mutated with LMO1 and LMO2. TAL1 was mutated in the SCID-X1 gene therapy-induced T-ALLs that had insertional mutation at LMO2. In contrast, LYL1 deregulation was infrequently concordant with LMO1 and occurred more commonly with LMO2[22], [39].