Bi-allelic truncating variants in ALPK3 (ALPK3tv) have been reported in small paediatric case series, presenting with a complex phenotype of dilated cardiomyopathy (DCM) often evolving into HCM with poor systolic function3–8 and common variants in ALPK3 have been associated with DCM and more recently HCM in genome-wide approaches.9–13. This evidence concerns the gene ALPK3 and familial dilated cardiomyopathy.