Interleukin‐6 (IL‐6) is a well‐documented growth factor and therapeutic target in plasma cell myeloma, and MISTRG mice that have been modified with an additional knock‐in allele encoding human IL‐6 (MISTRG6) support multiple myeloma engraftment and growth (Das et al, 2016). The gene discussed is IL6; the disease is AL amyloidosis.