Huntington’s gene has a specific part that is expanded in affected people. In all people, the extension of DNA has a pattern called “trinucleotides’ repetitions”. The nucleotides are bricks of DNA and they are indentified by G, C, A and T. In many people, the repetition pattern CAG is present no more than 30 times or less, while in case of disease, it’s present more than 36 times. Examining the DNA of the person and counting CAG number, it’s possible to know if the person will have the disease.
It’s possible to know if you are a carrier of mutation thanks to the genetic test, that consists in a simple taking of a blood sample. The minimum age for the genetic test in a person without symptoms is 18 years old. The decision to process the test is personal and it can’t be made with carelessness. A person at risk can’t be forced to know in advance its own destiny.
It’s important that people who want to process the test take it in a specialised medical centre, that provides for preparatory sessions and conversations with various professional roles: geneticist, neurologist and psychologist. The discussion about result and the remote control complete this procedure. Preparatory sessions must guarantee that the person realizes all the way potential implications of his genetic condition, picks in full awareness and is prepared to receive a possible positive result.
It’s essential to remember that, when you take the test, it’s not possible to establish neither when the disease will start, nor its course or its seriousness. People positive at test can stay healthy for a long time, because symptoms could start to show even after many years. If you want to have a family, the couple can ask the prenatal test of foetus or they can think of a pre-implantation.