MYBPC3 and cardiomyopathy: As shown by the examples of cardiomyopathy genes, the I-set (Pfam ID: PF07679) and FN3 (Pfam ID: PF00041) domains in MYBPC3 belong to large domain families with 785 and 597 homologous copies respectively in the exome, while domains from the other three tested genes belong to domain families with fewer than 72 copies in the exome (the largest domain family: EF-hand_1 (Pfam ID: PF00036) in MYL2).