The 46/1 haplotype predisposes individuals to somatic mutations in JAK2 and myeloproliferative neoplasms such as polycythemia vera (PV) via the JAK2 V617F somatic mutation.24,26 Unsurprisingly, given strong linkage disequilibrium between the vQTL and rs59384377, rs59384377 also had a significant negative interaction with rs35417585 (Supplementary Fig 4; P = 1.39x10−6). The gene discussed is JAK2; the disease is acquired polycythemia vera.