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ACY1 gene

aminoacylase 1

Normal Function

The ACY1 gene provides instructions for making an enzyme called aminoacylase 1, which is found in many tissues and organs, including the kidneys and the brain. This enzyme is involved in the breakdown of proteinswhen they are no longer needed. Many proteins in the body have a chemical group called an acetyl group attached to one end. This modification, called N-acetylation, helps protect and stabilize the protein. Aminoacylase 1 performs the final step in the breakdown of these proteins by removing the acetyl group from certain protein building blocks (amino acids). The amino acids can then be recycled and used to build other proteins.

Health Conditions Related to Genetic Changes

Aminoacylase 1 deficiency

Several mutations in the ACY1 gene have been identified in people with a condition called aminoacylase 1 deficiency. This condition is characterized by delayed development of mental and motor skills and other neurological problems, although some people with the condition have no signs or symptoms. Most of the associated ACY1 gene mutations change single amino acids in the aminoacylase 1 enzyme. These and other ACY1 gene mutations lead to production of an aminoacylase 1 enzyme with little or no function. Without this enzyme's function, acetyl groups are not efficiently removed from a subset of amino acids (including methionine, glutamic acid, alanine, serine, glycine, leucine, valine, threonine, and isoleucine) during the breakdown of proteins. The excess N-acetylated amino acids are released from the body in urine. It is not known how a reduction of aminoacylase 1 function leads to neurological problems in people with aminoacylase 1 deficiency.

More About This Health Condition

Other Names for This Gene

  • ACY-1
  • ACY1D
  • acylase 1
  • aminoacylase-1
  • N-acyl-L-amino-acid amidohydrolase

Additional Information & Resources

Tests Listed in the Genetic Testing Registry

Scientific Articles on PubMed

Catalog of Genes and Diseases from OMIM

Gene and Variant Databases


  • Ferri L, Funghini S, Fioravanti A, Biondi EG, la Marca G, Guerrini R, Donati MA, Morrone A. Aminoacylase I deficiency due to ACY1 mRNA exon skipping. Clin Genet. 2014 Oct;86(4):367-72. doi: 10.1111/cge.12297. Epub 2013 Nov 18. Citation on PubMed
  • Lindner HA, Lunin VV, Alary A, Hecker R, Cygler M, Menard R. Essential roles of zinc ligation and enzyme dimerization for catalysis in the aminoacylase-1/M20 family. J Biol Chem. 2003 Nov 7;278(45):44496-504. doi: 10.1074/jbc.M304233200. Epub 2003 Aug 21. Citation on PubMed
  • Perrier J, Durand A, Giardina T, Puigserver A. Catabolism of intracellular N-terminal acetylated proteins: involvement of acylpeptide hydrolase and acylase. Biochimie. 2005 Aug;87(8):673-85. doi: 10.1016/j.biochi.2005.04.002. Citation on PubMed
  • Sass JO, Mohr V, Olbrich H, Engelke U, Horvath J, Fliegauf M, Loges NT, Schweitzer-Krantz S, Moebus R, Weiler P, Kispert A, Superti-Furga A, Wevers RA, Omran H. Mutations in ACY1, the gene encoding aminoacylase 1, cause a novel inborn error of metabolism. Am J Hum Genet. 2006 Mar;78(3):401-9. doi: 10.1086/500563. Epub 2006 Jan 18. Citation on PubMed or Free article on PubMed Central
  • Sommer A, Christensen E, Schwenger S, Seul R, Haas D, Olbrich H, Omran H, Sass JO. The molecular basis of aminoacylase 1 deficiency. Biochim Biophys Acta. 2011 Jun;1812(6):685-90. doi: 10.1016/j.bbadis.2011.03.005. Epub 2011 Mar 23. Citation on PubMed
  • Van Coster RN, Gerlo EA, Giardina TG, Engelke UF, Smet JE, De Praeter CM, Meersschaut VA, De Meirleir LJ, Seneca SH, Devreese B, Leroy JG, Herga S, Perrier JP, Wevers RA, Lissens W. Aminoacylase I deficiency: a novel inborn error of metabolism. Biochem Biophys Res Commun. 2005 Dec 23;338(3):1322-6. doi: 10.1016/j.bbrc.2005.10.126. Epub 2005 Nov 2. Citation on PubMed

The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health.