For the LDB3 protein, RBM20 regulates differential inclusion of exon 4 (included in healthy humans or wild type (WT) rats) or exon 5 and 6 (included in the patient with RBM20 mutation or Rbm20 deficient rats), and the isoform switch of LDB3 has been related to DCM [18]. The gene discussed is LDB3; the disease is familial dilated cardiomyopathy.