Examples resolved by WGS from the current study include deep intronic variants in ASS1 causing citrullinemia, deletion of a complete exon in ARG1 causing arginase deficiency, and uniparental disomy with homozygous pathogenic variants in PCCA and HADHA, causing propionic aciduria and LCHAD deficiency, respectively. This evidence concerns the gene ASS1 and arginase deficiency.