ASPA and Canavan disease: GTA has also been tested as a treatment for the fatal genetic disease Canavan disease, which is caused by mutations in the gene for the NAA catabolizing enzyme aspartoacylase (ASPA), one of the aminoacylase enzymes that act to remove acetate from Nα-acetylated amino acids (see part 1 of this review for more details on NAA and ASPA).