Library · Disease
Huntington disease
Make it clearer
Huntington disease is a neurodegenerative disease, meaning one in which neurons are gradually lost. It is inherited in an autosomal dominant pattern: receiving the altered gene from just one parent is enough. It is recognized by a triad, three things that go together: involuntary and irregular choreic movements, changes in thinking, and changes in behavior.
The cause lies in a gene, the one for huntingtin. Inside it, three DNA letters, CAG, repeat many more times than normal. Because each CAG triplet is translated into an amino acid called glutamine, the protein ends up with an abnormally long polyglutamine expansion. One syllable of the gene repeats too many times, and the protein comes out with a tail that clumps.
That tail changes how the protein behaves: it becomes prone to aggregating and building up. And the damage concentrates in one place: the main feature of Huntington disease is degeneration of the neurons of the striatum, a group of nuclei deep inside the brain.
In brief
Huntington disease is an inherited autosomal dominant neurodegenerative disorder with involuntary choreic movements and cognitive and behavioral changes.
It is caused by CAG triplet repeats in the huntingtin gene, which abnormally lengthen a polyglutamine expansion.
One syllable of the gene repeats too many times, and the protein comes out with a tail that clumps.
That expansion makes the protein more prone to aggregation, and the main feature is degeneration of striatal neurons.
Sources (1)
- National Center for Biotechnology Information, StatPearls PublishingHuntington Disease, StatPearlsPublished
This page explains the topic in general terms; it does not tell anyone what treatment to follow.
Updated