TRANSMiSSiON

Huntington's disease (HD) is inherited by the child's parents. This disease arises from an expansion of a CAG trinucleotide repeat of chromosome 4. There are different levels that a person can have of CAG repeats that tells whether a person will have Huntington's disease. A person with a variant of atleast 36 repeats has a high possibility of having HD but fortunately many people have variants of 27 CAG or lower which measn they have almost no risk of getting HD or of passing it on to their children. People with variants between 27 and 35 CAG repeats called high normal are not at risk for the disease, but males in between these ranges are able to pass on expanded CAG repeats to their children which makes the child more at risk of developiong HD.