This interaction with PV is likely driven by JAK2 V617F clonal hematopoiesis, defined as a copy-neutral loss of heterozygosity of the p-arm of chromosome 9 or a somatic single nucleotide variant causing JAK2 V617F CHIP.27–29 Among 29,965 homozygotes for the JAK2 46/1 haplotype, each additional copy of the rs35417585 alternate allele reduced risk of JAK2 V617F clonal hematopoiesis by 1.25-fold (95% CI = [1.12, 1.75]). This evidence concerns the gene JAK2 and acquired polycythemia vera.