The ACAT1 gene encodes a mitochondrial enzyme of 427 amino acids called acetyl-Coenzyme A acetyltransferase (ACAT1), also known as 2-methylacetoacetyl CoA thiolase or beta-ketothiolase. This enzyme is involved in both amino acid degradation and in fatty acid oxidation. It plays an important role in ketone body metabolism and catalyzes the reversible formation of acetoacetyl-CoA from two molecules of acetyl-CoA.
In a retrospective analysis of IEMs diagnosed over a 12-year period (1998-2010) in a hospital in Lebanon, Karam et al. (2013) found three patients diagnosed with Acetyl-CoA Thiolase Deficiency. The median age of diagnosis was 3-years.