The frequency of NK cells showed a decreasing trend (mean(MPN) = 8% vs mean(HC) = 14%; p = 0.095) in MPN patients, but no differences were observed in the frequencies of T cells, B cells, CD3+/CD56+ cells, or T cell subsets (Supplemental Figure 4B). This evidence concerns the gene NCAM1 and myeloproliferative neoplasm.