A gene is a piece of biological information you inherit from your parents. It is present in every cell of the body and tells cells what to do. Genes control cells by producing proteins; each gene is really a kind of recipe for making a certain protein.
Genes are usually attached to a chromosome (a strand of DNA containing many different genes). Each human cell contains around 25,000 genes and most have 23 pairs of chromosomes. Chromosomes come in pairs because we inherit one from each parent.
It is the same gene that determines whether you will develop Huntington’s disease or Juvenile Huntington’s disease. Everyone has it and it’s called the Huntington’s gene. It’s found on chromosome pair number 4. However, people that develop either adult or Juvenile Huntington’s have an important difference or ‘fault’ in their Huntington’s gene.
If a child who has a parent with the Huntington's gene starts to show symptoms of Juvenile Huntington’s, and if there is a strong suspicion that they may have it, a diagnostic blood test may be done to see if they do have it.
However, because Juvenile Huntington’s is so rare and because its symptoms can be hard to recognise, it can often take a long time before a definite diagnosis is established. Not knowing can be stressful, but support is available to help you through this situation.
We have an experienced specialist adviser on Juvenile Huntington’s, Helen Santini. She will be happy to answer any questions you have. You can reach her on firstname.lastname@example.org or 01279 507656.