[Analysis of ARID1B gene variant in a patient with mental retardation and ejaculatory dysfunction].

OBJECTIVE

To explore the clinical characteristics and genetic etiology of a patient with mental retardation and ejaculatory dysfunction.

METHODS

A patient with mental retardation and ejaculatory dysfunction who was admitted to the First Affiliated Hospital of Air Force Military Medical University on November 18, 2021 was selected as the study subject. Clinical data of the patient were collected. Peripheral venous blood samples were collected from the patient and his parents. Whole exome sequencing (WES) was carried out for the patient, and the candidate variant was verified by Sanger sequencing and bioinformatic analysis.

RESULTS

The patient, a 26-year-old male, had manifested atypical mental retardation and ejaculatory dysfunction. WES revealed that he has harbored a heterozygous variant of the ARID1B gene, namely c.5776C>T (p.Arg1926X). Sanger sequencing verified that neither of his parents has carried the same variant. The variant has been recorded in the 1000 Genomes, ExAC, gnomAD and ClinVar databases. A search of the dbSNP database suggested that the variant has a population frequency of 0.000 4%. The variant was predicted as deleterious by online software including Mutation Taster, CADD, and MutPred. Analysis with Cluster Omega online software suggested that the amino acid encoded by the variant site was highly conserved among various species. Analysis with PyMOL software suggested that the variant may affect the function of the encoded protein. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG) and ClinGen, the variant was predicted to be pathogenic.

CONCLUSION

The c.5776C>T (p.Arg1926X) variant of the ARID1B gene probably underlay the mental retardation and ejaculatory dysfunction in this patient. Above finding has broadened the spectrum of the ARID1B gene variants and provided reference for the diagnosis and treatment of the patient.