In MS, both an magnification (Kumar et al. 2006) and reduction (Venken et al. 2008) in FOXP3+ Treg were observed, and in rheumatoid arthritis and newly diagnosed T1D (type 1 diabetes), an increase in FOXP3+ Treg was found (Han et al. 2008; Marwaha et al. 2010). The gene discussed is FOXP3; the disease is myeloid sarcoma.