Detection of Genetic Variations in Children with Tetralogy of Fallot Using Whole Exome Sequencing Technology...

Background: Tetralogy of Fallot (TOF) is the most common cyanotic heart defect in newborns, with a complex etiology and genetic variation considered to be one of the main pathogenic factors. Identifying genetic variations associated with TOF has important clinical value for understanding its pathogenesis, patient susceptibility, and prognosis of patients with TOF. Therefore, this study aimed to identify potential pathogenic genes of TOF through comprehensive genetic analysis. Materials and Methods: In this study, we employed whole exome sequencing (WES) of the DNA of 47 Chinese children who received surgical TOF treatment at the Children's Hospital of Zhejiang University of Medicine and processed for DNA extraction and quantification of the DNA following WES using the Illumina NovaSeq platform. WES data undergo strict quality control and analysis processes including alignment, postprocessing, variant calling, annotation, and prioritization. Key tools, such as GATK's haplotype calling module and Annotate Variation, were used for variant annotation. In addition, by combining bioinformatics tools such as SIFT, Polyphen2, and Clin Pred, we evaluated the potential impact of nonsynonymous mutations on protein function and referred to relevant literature to support our prediction. Results: Comprehensive data analysis and quality assessment analysis corroborated the data generated from the WES dataset of 47 patients with TOF. Interpreting variants from the perspective of clinical pathogenicity results revealed a novel polymorphism and variant associated with TOF. The identified genetic results revealed evidence for a major contribution of MUTYH, RARB, GFM1, PDZD2, CEP57, DCPS, POMT2, BUB1B, CYP19A1, MAZ, USP10, and TCF3 and provided novel findings for functionally interacting proteins associated with the pathomechanism of TOF. Seven pathogenic variants related to TOF were detected, most of which were previously unreported in this cohort. Conclusions: The genetic variations discovered in this study emphasize the importance of genetic factors in the pathogenesis of TOF, revealing its complex molecular pathways and protein-protein interactions. The study of genetic diversity provides a new perspective for understanding the etiology of TOF and promotes an in-depth exploration of its pathological mechanisms. These findings lay the foundation for subsequent clinical research and the development of treatment strategies.