Analysis of clinical and genetic characteristics in a patient with Beck-Fahrner syndrome due to a frameshift variant of TET3 gene.
10.3760/cma.j.cn511374-20241019-00547
- Author:
Xiaoyan XUAN
1
,
2
;
Xiaoke ZHAO
;
Jun LI
Author Information
1. Department of Critical Care Medicine, Children's Hospital of Nanjing Medical University, Nanjing, Jiangsu 210008, China. lijunnu@
2. com.
- Publication Type:English Abstract
- MeSH:
Humans;
Male;
Frameshift Mutation;
Infant;
Dioxygenases/genetics*;
Exome Sequencing;
Female;
Proto-Oncogene Proteins/genetics*;
Pedigree
- From:
Chinese Journal of Medical Genetics
2025;42(10):1259-1264
- CountryChina
- Language:Chinese
-
Abstract:
OBJECTIVE:To explore the clinical and genetic characteristics of a patient with Beck-Fahrner syndrome attributed to a TET3 gene variants.
METHODS:A case of Beck-Fahrner syndrome (proband) who was treated at the Children's Hospital of Nanjing Medical University in December 2021 was selected as the study subject. Clinical data of the family were collected. Peripheral blood samples of the proband and his parents were collected, and genomic DNA was extracted for whole exome sequencing (WES). Candidate variants were verified in the family by Sanger sequencing. According to the "Classification Criteria and Guidelines for Genetic Variations" formulated by the American College of Medical Genetics and Genomics (hereinafter referred to as "ACMG guidelines"), the pathogenicity of the TET3 gene variant sites was rated. This study was approved by the Medical Ethics Committee of the Children's Hospital of Nanjing Medical University (Ethics No.: 202402022-1).
RESULTS:The proband was a male, with a age of 9 months at the time of consultation. His clinical manifestations included decreased muscle tone, global developmental delay, long face, and open mouth. WES revealed that he has harbored a c.2811_c.2812insAGAC (p.T938fs*27) (NM_001287491) truncation variant in exon 7 of the TET3 gene. Sanger sequencing showed that neither of his parents has harbored the same variant. According to the ACMG guidelines, the variant was rated as pathogenic (PVS1+PS2+PM2_Supporting).
CONCLUSION:The TET3 gene c.2811_c.2812insAGAC variant probably underlay the pathogenesis of Beck-Fahrner syndrome in the proband. Above discovery has enriched the mutational spectrum of the TET3 gene and provided a reference for the diagnosis and treatment of this disease.
