TANGO2-related metabolic encephalopathy and arrhythmias is caused by variations in the transport and Golgi organization 2 (TANGO2) gene. Genes provide instructions for creating proteins that play a critical role in many functions of the body.
When a mutation of a gene occurs, the protein product may be faulty, inefficient, absent, or overproduced. Depending upon the functions of the particular protein, this can affect many organ systems of the body, including the brain. Researchers are not sure what the protein produced (encoded) by the TANGO2 gene does. It may have a role in secretory protein loading within the endoplasmic reticulum, which is an extensive membrane network found within certain cells where proteins are processed.
The penetrance of disease causing variations in the TANGO2 gene is believed to be 100%. That means everyone who has disease causing changes in both copies of the TANGO2 gene will eventually develop some type of associated sign or symptom of the disorder. Variations in this gene also have variable expressivity, which means the signs and symptoms can differ among affected individuals. Consequently, the severity of the disorder will vary among affected individuals.
Genetic diseases are determined by the combination of genes for a particular trait that are on the chromosomes received from the father and the mother. Tango2 is inherited in a recessive pattern. Two carrier parents can both pass the defective gene on, the chance of an affected child is 25% with each pregnancy. The risk to have a child who is a carrier like the parents is 50% with each pregnancy. The chance for a child to receive normal genes from both parents and be genetically normal for that particular trait is 25%. The risk is the same for males and females.
