In 2014, Warkentin et al. [15] proposed a set of diagnostic criteria for spontaneous HIT, including thrombocytopenia without an alternative explanation, thrombosis, no recent heparin exposure, strongly positive PF4-dependent enzyme immunoassays (EIAs) in at least two different assays, and a strongly positive platelet activation assay with both heparin-independent and heparin-dependent activation. The gene discussed is PF4; the disease is Thrombocytopenia.