NSD2 and familial dilated cardiomyopathy: STZ injection was used to establish a mouse model of DCM, and qPCR analysis confirmed upregulation of several DDR‐related genes, including RAD51, BRCA2, DNA2, FANCD2, MSH6, TDP1, NSD2, PARP1, and BARD1, in diabetic mice compared to controls (Figure 1I).