TXNIP and myeloid sarcoma: The transcript showing the most significant induction in twins with MS compared with unaffected twins was TXNIP, which encodes thioredoxin-interacting protein (also known as vitamin D3 upregulated protein 1), a key mediator of the cellular antioxidant system that has been reported to regulate the responsiveness of T cells to IL-2 (ref. 28) (Extended Data Fig. 5g, Supplementary Table 5).