A novel de novo CASZ1 heterozygous frameshift variant causes dilated cardiomyopathy and left ventricular noncompaction cardiomyopathy

Abstract

Background: Dilated cardiomyopathy (DCM) is the most common cardiomyopathy with a common presentation of heart failure. It has been reported that CASZ1 loss-of-function mutation contributes to familial DCM and congenital ventricular septal defect (VSD). To date, only two pathogenic variants in CASZ1 have been previously reported worldwide. Methods: To identify the causative variant in an 11-month-old Chinese boy with DCM and left ventricular noncompaction cardiomyopathy (LVNC), trio-whole-exome sequencing was performed followed by mutational analysis and Sanger sequencing. Results: An unreported de novo heterozygous frameshift variant (c.2443_2459delGTGGGCACCCCCAGCCT, p.Val815Profs*14) in CASZ1 was idenitified in the proband. The frameshift mutation in CASZ1 not only led to DCM but also presented an LVNC phenotype. Conclusion: We have identified a novel CASZ1 variant in a patient with combined DCM and LVNC for the first time, thus broadening the phenotypic spectrum of CASZ1 variants. Furthermore, this study emphasized the usefulness of whole-exome sequencing for genetic diagnosis of cardiomyopathy.