In DCM, groupings of killer lectin receptor (KLR; KLRB1, KLRC1, and KLRF1) and granzyme (GZM; GZMA, GZMB, and GZMK) genes are upregulated to a greater extent compared to PPCM and donors. The gene discussed is KLRB1; the disease is familial dilated cardiomyopathy.