So far, DCM has been described in FKRP‐CDG, FKTN‐CDG, POMT1‐CDG, POMT2‐CDG, DOLK‐CDG, DPM3‐CDG, and PGM1‐CDG.19, 22 With the exception of PGM1‐CDG, these CDGs are associated with abnormal O‐mannosylation of αDG. Here, POMT2 is linked to familial dilated cardiomyopathy.