Diagnosis is typically post-mortem. Classification There are five known subgroups of MGA; MGA type I, II, III, IV & V. Type OMIM Gene Locus Also known as/Description Genetics Type I AUH Chr.9<unk>  type I,<unk><unk>  acidemia or<unk> -Methylglutaconyl-CoA Hydratase Deficiency Mutations in the AUH gene cause<unk>  type I. This gene provides instructions for producing<unk> -methylglutaconyl-CoA hydratase, an enzyme that is involved in processing the amino acid leucine. This amino acid is broken down in the mitochondria during the process of energy production. A deficiency of this enzyme leads to a buildup of<unk><unk>  acid, which is eliminated in the urine. Researchers believe that other genes or environmental factors also contribute to the development of this disorder. Type II TAZ Xq28 Barth syndrome (BTHS),<unk>  type II or Cardiomyopathy-neutropenia syndrome Mutations in the TAZ gene cause<unk>  type II (Barth syndrome). This gene provides instructions for making a protein called tafazzin. This protein plays a critical role in maintaining the levels of a particular lipid, called cardiolipin, located in the inner membrane of the mitochondria. A lack of tafazzin results in abnormalities in the structure and function of mitochondria, leading to the heart defects and other problems seen in this disorder. Type III OPA3 19q13.2-q13.3<unk>  type III or Costeff syndrome Mutations in the OPA3 gene cause<unk>  type III. This gene carries instructions for making a protein that is also found in mitochondria, but whose function is unknown. Researchers have suggested that cells with a defective OPA3 protein are more susceptible to a process that eliminates damaged or unneeded cells (so-called apoptosis). Type IV ? ?<unk>  type IV Type V DNAJC19<unk> q26.3<unk>  type V The characteristic features of<unk>  type I include speech delay, delayed development of both mental and motor skills (psychomotor delay), elevated levels of acid in the blood and tissues (metabolic acidosis), abnormal muscle tone (dystonia), and spasms and weakness affecting the arms and legs (spastic quadriparesis). Fewer than 20 cases of<unk>  type I have been reported. Barth syndrome is a common name for<unk>  type II. The main features of Barth syndrome include a weakened and enlarged heart (dilated cardiomyopathy), recurrent infections due to low numbers of white blood cells (neutropenia), skeletal problems, and delayed growth. The incidence of<unk>  type II is approximately 1 in 200,000 male infants. Costeff syndrome is another name for<unk>  type III. This disorder is characterized mainly by the degeneration of the optic nerves, which carry information from the eyes to the brain. Sometimes other nervous system problems occur, such as an inability to maintain posture, poor muscle tone, the development of certain involuntary movements (extrapyramidal dysfunction), and a general decrease in brain function (cognitive deficit). The incidence of<unk>  type III is about 1 in 10,000 newborns in the Iraqi Jewish population. This disorder is extremely rare in all other populations. The signs and symptoms of<unk>  type IV are variable and overlap with types I-III. The incidence of<unk>  type IV is unknown.
3-Methylglutaconic aciduria
Urocanic aciduria
Hawkinsinuria
Alpha-aminoadipic and alpha-ketoadipic aciduria
Homocystinuria
2-Hydroxyglutaric aciduria
Cystathioninuria
Phenylketonuria