Objective: To explore the clinical and genetic features of a patient with mental retardation.
Methods: G-Banding chromosomal karyotyping and high-throughput sequencing was carried out for the child. Suspected variant was validated in his family by Sanger sequencing and bioinformatic analysis.
Results: The patient was found to carry a de novo heterozygous c.4090G>T (p.Gly1364X) variant of the ASXL3 gene, which was known to predispose to Bainbridge-Ropers syndrome.
Conclusion: The nonsense c.4090G>T (p.Gly1364X) variant probably accounts for the disease in this patient.