A novel de novo RNF13 variant in developmental and epileptic encephalopathy 73: genotype–phenotype correlation and literature review

BACKGROUND: Developmental and epileptic encephalopathy-73 (DEE73, OMIM: #618379) is a rare autosomal dominant genetic disorder. This study reports a novel de novo RNF13 variant in a Chinese patient, aiming to assess its pathogenicity and expand understanding of the phenotypic and molecular spectrum of DEE73. METHODS: Whole-exome sequencing was performed on the patient to identify candidate variants associated with the clinical phenotype. Putative pathogenic variants were validated by Sanger sequencing. In silico prediction tools were used to assess the functional impact of the identified variant. A literature review was conducted to summarize the clinical features of the 7 previously reported cases of DEE73. RESULTS: A novel likely pathogenic frameshift variant, c.929del/p.(Pro310fs*3), in RNF13 was identified in the patient. The clinical presentation was consistent with the diagnostic features of DEE73, yet also exhibited phenotypic heterogeneity, including severe scoliosis and pectus carinatum. A literature review confirmed that the core clinical features of DEE73 include microcephaly, seizures, developmental delay, joint contractures, abnormal muscle tone and electroencephalogram abnormalities. CONCLUSIONS: This study expands the known genetic spectrum of DEE73 and enhances the understanding of phenotypic characteristics associated with RNF13 variants. The findings have important implications for improving variant-based screening, genetic diagnosis, and insights into the molecular mechanisms of RNF13-related disorders.