A striking characteristic of X-linked inheritance is that fathers cannot pass X-linked traits to their sons. The inheritance pattern of 3-methylglutaconic aciduria type IV is unknown. Diagnosis
Diagnosis is typically post-mortem. Classification
There are five known subgroups of MGA; MGA type I, II, III, IV & V.

The characteristic features of 3-methylglutaconic aciduria 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 3-methylglutaconic aciduria type I have been reported. Barth syndrome is a common name for 3-methylglutaconic aciduria 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 3-methylglutaconic aciduria type II is approximately 1 in 200,000 male infants. Costeff syndrome is another name for 3-methylglutaconic aciduria 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 3-methylglutaconic aciduria type III is about 1 in 10,000 newborns in the Iraqi Jewish population. This disorder is extremely rare in all other populations.
Capillaritis is where the capillaries, usually of the legs or lungs, are inflamed, allowing blood cells to pass through.It may occur in the lungs as pulmonary capillaritis, or in the skin as pigmented purpuric dermatosis. Capillaritis usually affects otherwise healthy people. Capillaritis can take many forms but is made up of tiny red or brown dots that may be spread out or in a group forming a red or brown patch on the skin. One variation, Majocchi purpupa,  forms concentric rings.Capillaritis is a mild condition not requiring treatment. There is no known cure, however capillaritis can disappear within a few weeks, recur from time to time, or persist for years. == References ==