A novel ASXL3 gene variant in a Chinese Boy causing Bainbridge

Bainbridge-Ropers syndrome (BRPS) is an uncommon genetic disorder characterized by developmental delay, intellectual disability, distinctive facial features, and various congenital anomalies primarily attributed to mutations in the Additional Sex Combs Like 3 (ASXL3) gene. In this case report, we employed Next-Generation Sequencing techniques for genetic analysis to investigate the clinical phenotype, imaging manifestations, and genetic characteristics of BPRS syndrome caused by ASXL3 gene mutation to enhance our understanding of BPRS and its underlying genetic factors.

This study presents a case of an infant male, aged 4 months and 6 days, who was referred to our hospital with symptoms including fever, cough, and wheezing. The patient had a history of constitutional weakness, previous hospitalizations for respiratory distress, and treatment with continuous positive airway pressure (CPAP). Whole exome sequencing identified a de novo heterozygous ASXL3 gene variant located on chromosome 18 (chr18:31318777-31318779; NM_030632.3; exon 11), described as c.1409_1411delinsTT (p. His470Leufs*14), resulting in a frameshift mutation leading to the diagnosis of BRPS. This variant was classified as pathogenic based on ACMG guidelines.

To the best of our knowledge, this variant in the patient has not been reported previously in the literature. This study presents a novel case of the ASXL3 gene variant, emphasizing the significance of genetic analysis in patients with complex clinical presentations. Moreover, it underscores the imperative need for further research on the genetic underpinnings of rare diseases.