In all three investigated groups (NBM, MDS, and AML), the percentage of NK cells expressing CD159a increased from the immature (CD56bright CD94hi CD16- CD57-) to mature (CD56dim CD94med CD16+ CD57-) NK state, but then dropped in the hypermature (CD56dim CD94low CD16+ CD57+) NK stage only in the NBM (mature and hypermature: P <0.0001, Supplementary Figure 4A) and MDS (mature and hypermature: P = 0.0138, Supplementary Figure 4B) cases (Supplementary Table 6 and Figures 5A–C). Here, KLRC1 is linked to myelodysplastic syndrome.