First, LMO2 expression due to retroviral insertion and transactivation in CD34+ HSCs of X‐SCID patients caused T‐ALL but no other hematopoietic tumors (Hacein‐Bey‐Abina et al, 2008; Howe et al, 2008). Here, LMO2 is linked to hematopoietic and lymphoid cell neoplasm.