We searched each genome for evidence of additional rare variants causative of or substantially contributory to the observed cardiomyopathy phenotype and found rare protein altering variants in multiple genes and individuals, including an early termination variant in the cardiomyopathy associated gene FLNC. A VUS in FLNC in the presence of a VUS in MYBPC3 has previously been suggested as a potential modifier of HCM (75). This evidence concerns the gene MYBPC3 and cardiomyopathy.