Interestingly, some of them play a role in IFN-mediated pathways, e.g. TYK2 and STAT4, and show aberrant expression in MS when compared to the healthy population, with TYK2 upregulated in PBMC from progressive MS and STAT4 downregulated in early and progressive stages of MS9. The gene discussed is TYK2; the disease is myeloid sarcoma.