A Novel Missense Variant in the TCOF1 Gene in one Chinese Case With Treacher Collins Syndrome

Abstract

Objective

The purpose of this study is to analyze the clinical characteristics of a Treacher Collins syndrome (TCS) patient carrying a de novo variant of TCOF1, and briefly analyze the correlation between genetic results and clinical features. Also, the pathogenesis and clinical treatment of TCS are reviewed.

Design

A Chinese pedigree with TCS containing 8 members was enrolled. Phenotype of the proband was evaluated by a surgeon, then whole exome sequencing of the proband was performed. Then we verified the proband-derived variants by Sanger sequencing in the pedigree. Correlation between genotype and phenotype was analyzed.

Setting

The study was conducted in a stomatological hospital.

Patients, participants

A Chinese pedigree with TCS containing 8 members.

Main outcome measures

To ascertain the genetic variants in the Chinese pedigree with TCS.

Interventions

Blood samples were collected.

Results

We reported a case of typical TCS with a de novo missense variant (NM_001371623.1:c.38T>G, p.(Leu13Arg)) in exon 1 of TCOF1, who presented asymmetrical facial abnormalities, including downward slanting of the palpebral fissures, sparse eyebrows, lateral tilt of the eyeballs, bilateral external ears deformities, hypoplasia of midface, reduction of the zygomatic body, bilateral orbital invagination, right external auditory canal atresia, mandibular ramus short deformity, cleft palate and the whole face was convex.

Conclusions

This research found a novel variant of TCS in Chinese, expanding the spectrum of TCS pathogenic variants. Genetic results combined with clinical phenotype can make a definite diagnosis and provide genetic counseling for the family.

Keywords

Treacher Collins syndrome variant

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