For trio whole‐exome sequencing (WES), genomic DNA was extracted from the proband and their parents using a DNA extraction kit (Tiangen, Beijing, China), and the purity and concentration of DNA samples were determined to 50–250 ng/μL using a nucleic acid quantification instrument (Nanodrop2000) and stored at −20°C. The xGen Exome Research Panel v2.0 (IDT, USA) was used for exome library constructing, followed by next‐generation sequencing on the NovaSeq 6000 series sequencer (Illumina, USA). Data cleaning and quality control were performed following the manufacturer's instructions. Burrows‐Wheeler Aligner was used for aligning the reads to the Ensemble GRCh37/hg19 reference genome. Base quality score recalibration together with SNP and short indel calling was conducted using the GATK software package. PolyPhen2 and MutationTaster software was applied for protein function prediction and the pathogenicity of genetic variants was annotated according to the American College of Medical Genetics and Genomics (ACMG) clinical practice guidelines (Richards et al., 2015 (link)). The predicted structure of IARS1 (PDB: AF‐P41252‐F1) was downloaded from AlphaFold Protein Structure Database (https://alphafold.ebi.ac.uk/) (Jumper et al., 2021 (link)). The constructed model structure was visualized and analyzed using PyMOL software(www.pymol.org).