Abstract
Neonatal dilated cardiomyopathy (DCM) is rare with high etiologic heterogeneity. Recently, biallelic, autosomal recessive, pathogenic variants in RPL3L (ribosomal protein L3-like) have been reported in the literature with severe early-onset DCM. In the present brief report, we identified two pathogenic RPL3L variants, each harbored in unaffected heterozygous parents: mother (RPL3L c.1076_1080delCCGTG (p.Ala359Glyfs*4)) and father (RPL3L c.80G > A (p.Gly27Asp)). Pathogenic variants were segregated as autosomal recessive to two offspring born with compound heterozygous RPL3L variants and affected by neonatal DCM. This is the second report in the literature to the best of our knowledge and our findings support the pathogenicity of biallelic RPL3L pathologic variants associated with rapidly progressive neonatal DCM and heart failure with a poor prognosis.