Several studies have investigated a possible involvement of the genes responsible for Familiar Mediterranean Fever (FMF, gene MEFV), TNF-Receptor Associated Periodic Syndrome (TRAPS, gene TNFRSF1A) Hyper IgD Syndrome (HIDS, gene MVK) and Cryopyrin Associated Periodic Syndrome (CAPS, gene NLRP3) in PFAPA cohorts11, 17, 18, 19, 20, 21. The gene discussed is MEFV; the disease is PFAPA syndrome.