In the present study, 8.7% of the patients with PV (4/46) had pathogenic CNVs detected using multigene panel testing: one Alu insertion in BRCA2 (c.156_157insAlu), one BRCA1 exon 8–19 deletion, one PALB2 exon 2–3 deletion, and one TP53 partial deletion of exon 5. This evidence concerns the gene BRCA1 and acquired polycythemia vera.