RESUMO
Objective:To investigate the clinical phenotype and gene mutation in a child with developmental disorders caused by CTNNB1 gene mutation. Methods:Clinical data of a child with CTNNB1 gene mutation who was admitted to Xiamen Hospital of Fudan University Affiliated Pediatric Hospital in May 2017 were collected, whole exome sequencing technology was applied to verify the family lineage of the child, and the pathogenicity of mutation site was analyzed. Results:The patient was a 6 years and 1 month old male, with a clinical phenotype including mental retardation, motor developmental disorders, speech disorders, visual disorders (internal strabismus), microcephaly, and behavioral problems (social withdrawal, overdependence, etc.), as well as panic syndrome (i.e., sudden shrieking in response to auditory and visual stimuli, extensional rigidity of the body, etc., followed by short periods of general extensional rigidity). The whole exome sequencing results showed the presence of a de novo mutation c.283(exon4)C>T in the CTNNB1 gene, and the c.283(exon4)C>T mutation was interpreted as pathogenic (PVS1+PS2+PS1+PM2+PM) according to the American College of Medical Genetics and Genomics variant classification criteria and guidelines. No relevant genetic variants were found in the parental family verification. Conclusion:CTNNB1 gene mutation c.283(exon4)C>T can cause neurodevelopmental disorders, including mental retardation, motor developmental disorders, speech disorders, visual disorders, microcephaly and behavioral abnormalities.