Th1 and Th2 are subsets of T cells which are involved in the cellular immune response, in which Th1 is involved in the elimination of foreign bodies with IFN-γ as their primary cytokine, while Th2 is involved in atopy and anti-inflammatory response, producing interleukins (IL) 4, 5, 10 and 13 A case in point is a study reporting a skewed in T helper polarisation towards a Th2 type of immune response in 114 ME/CFS patients. The gene discussed is IFNG; the disease is myalgic encephalomeyelitis/chronic fatigue syndrome.