A review of aromatic l-amino acid decarboxylase (AADC) deficiency in Taiwan

Am J Med Genet C Semin Med Genet. 2019 Jun;181(2):226-229. doi: 10.1002/ajmg.c.31670. Epub 2019 Jan 7.

Abstract

Aromatic l-amino acid decarboxylase deficiency (AADCD) is a rare inherited disease prevalent in South East Asia. This disease is due to the founder mutation IVS 6 + 4A > T (c.714 + 4A > T), which accounts for most alleles. Patients with this mutation have severe phenotypes. About 90 % of these patients in South East Asia do not have head control and cannot sit, stand, or speak from birth to the time of observation. In 2012, a gene study to treat these patients with intraputamen injection of adeno-associated virus2-human AADC showed prominent motor improvement and an increased PDMS-2 score 12 months after treatment. In addition, systemic gene therapy in a mouse model of AADCD achieved widespread correction of the Ddc gene. In this article, we review the natural history, clinical course, and treatment effects seen in these clinical and mouse studies. Future studies focusing on noninvasive viral vector delivery or alternative emerging treatments may also benefit patients with AADCD.

Keywords: AADC deficiency; adeno-associated virus; animal model; clinical trial; gene therapy; splicing mutation.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Amino Acid Metabolism, Inborn Errors / genetics*
  • Amino Acid Metabolism, Inborn Errors / therapy*
  • Animals
  • Aromatic-L-Amino-Acid Decarboxylases / deficiency*
  • Aromatic-L-Amino-Acid Decarboxylases / genetics
  • Aromatic-L-Amino-Acid Decarboxylases / therapeutic use
  • Founder Effect
  • Genetic Therapy / methods*
  • Humans
  • Mice
  • Mutation*
  • Taiwan

Substances

  • Aromatic-L-Amino-Acid Decarboxylases

Supplementary concepts

  • Aromatic amino acid decarboxylase deficiency