3-methylglutaconic aciduria (3MGA) is a group of 5 genetic disorders that result in the inability of the body to get energy from proteins in the body. Proteins are made of building blocks called amino acids. Under normal conditions, both proteins and amino acids can be used for energy to support muscles and growth. Symptoms of 3MGA vary depending on the specific disorder but can include delayed growth, muscle weakness (hypotonia), and muscle spasms. These symptoms are present at birth.
3MGA disorders are caused by a mutation (change) to a variety of genes. All of these mutations cause different proteins to be missing which are necessary to break down other proteins or amino acids. The missing proteins are normally present in the mitochondria, the part of the cell that is responsible for producing energy. 3MGA is therefore a type of mitochondrial disease. 3MGA also causes harmful organic acids to build up in the body, making it an organic acid condition as well. All 3MGA disorders are inherited, but the method of inheritance varies by type. More information about each variation can be found on Disease InfoSearch by searching the specific name of that variation.
In order to diagnose 3MGA, a medical professional will often test a blood or urine sample for a high level of organic acids. The doctor will then likely order genetic testing to confirm the diagnosis. Treatment options depend on the presented symptoms and therefore vary by type of 3MGA. Many babies are screened for 3MGA disorders at birth so that treatment can begin early, however the conditions included in newborn screening differ from state to state. For more information, visit Baby’s First Test. Talk with your baby’s doctor to determine the most current treatment options. Genetic counselors and support groups are also a good source of information.