Aminoacylase 1 deficient individuals are characterized by elevated urinary levels of several N-acylated amino acids (as detected by organic acid analysis) without an increase in N-acetylaspartate. Aminoacylase 1 deficiency is caused by biallelic pathogenic variants in ACY1. ACY1 encodes the enzyme Aminoacylase 1 which catalyses the hydrolysis of N-acylated amino acids. The diagnosis can be confirmed by reduced enzyme activity tests in patient-derived Epstein-Barr virus (EBV)-transformed lymphoblasts or cultured fibroblasts or mutation analysis. c.1057C>T (p.Arg353Cys) is the most frequently observed ACY1 variant that underlies aminoacylase 1 deficiency.
ACY1