Among the possible candidate genes included in locus ETM2, the rs11680700 variant within the HS1BP3 gene (HCLS1 binding protein 3, MIM 609359, gene ID 64342) was described in two families with ET [55], and in 12 of 73 (16.4%) patients with familial ET unrelated among them, while this variant was absent in 304 healthy controls [55,56]. The gene discussed is HS1BP3; the disease is essential thrombocythemia.