Identification of potential pathogenic mutations in Chinese children with first branchial cleft anomalies detected by whole-exome sequencing

Importance:First branchial cleft anomalies(FBCAs)are rare congenital malformations,accounting for<8%of all branchial cleft anomalies.However,little is currently known about the cause of FBCAs at the molecular level.Objective:To identify genomic alterations related to the genetic etiology of FBCAs in Chinese children.Methods:We performed whole-exome sequencing of samples from 10 pediatric patients with FBCAs.Data analysis was carried out using the Burrow-Wheeler Alignment software package,and the dbSNP database for comparisons.Rare variants were further validated by Sanger sequencing.Insertion/deletions(indels)were examined using the Genome Analysis Toolkit.Results:We identified 14 non-synonymous mutations in seven potential FBCA-susceptibility genes(TRAPPC12,NRP2,NPNT,SH3RF2,RHPN1,TENM4,and ARMCX4).We also detected 133 shared small indels in 125 genes.Gene Ontology analysis indicated that most of the identified genes played critical roles in development and differentiation pathways involved in regulating organ development.Interpretation:We characterized the mutational landscape in pathways involved in development and differentiation in Chinese children with FBCA.The results identified potential pathogenic genes and mutations related to FBCA,and provide molecular-level support for the branchial theory of FBCA pathogenesis.

First branchial cleft cyst accompanied by external auditory canal atresia and middle ear malformation:A case report

BACKGROUND We report a rare case of first branchial cleft anomaly(FBCA)accompanied by bony atresia of the external auditory canal,middle ear malformation,and location malformation of the facial nerve according to the intraoperative findings.CASE SUMMARY A 19-year-old male patient presented to our department with a mass behind the right earlobe and recurrent postauricular swelling and pain since childhood,he also had severe hearing loss in the right ear since birth.The patient underwent surgery including mass removal,mastoidectomy,and simultaneous meatoplasty and ossiculoplasty under microscopy.No facial palsy or recurrence was noted during postoperative follow-up.CONCLUSION FBCAs are rare,and to our knowledge,this is the first report of FBCA accompanied by external auditory canal bony atresia,middle ear malformation,and location malformation of the facial nerve.An effective postauricular approach under microscopy facilitated complete lesion removal and simultaneous otologic reconstruction.