We found ppcTnI to be the predominant cTnI proteoform in the non-diseased donor heart (Fig. 2f), whereas non-phosphorylated cTnI was found to be the most abundant cTnI proteoform in the dilated cardiomyopathy heart (Fig. 2g), consistent with previous reports suggesting phosphorylation of cTnI as a potential biomarker for heart diseases27,31,32. The gene discussed is TNNI3; the disease is dilated cardiomyopathy.