What is HD?
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available for young people, parents and
professionals on our site:
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Huntington’s disease is a genetic disorder which is caused by an expanded gene in a person’s
DNA. Everybody has the gene that causes Huntington’s disease, but people that develop the
condition have a longer version of the gene. It is that expansion which causes the gene not to
work properly and eventually causes people to develop the condition.
Huntington’s disease is also a ‘neurodegenerative disorder’. But what does neurodegenerative
disorder actually mean?! Well, if you break it down, neuro means ‘nerve’ and degenerative
means something that gradually gets worse. Disorder is another word for a condition, or
disease. So when people say Huntington’s is a neurodegenerative disorder, they are saying that
Huntington’s is a condition which affects the nervous system and gradually gets worse over
time. This means the condition affects the cells of our brains and continues to cause damage as
time progresses which stops the brain and body from working as well as they used to. As a
result, people develop symptoms of Huntington’s disease. These symptoms can be divided into
three main types: involuntary movements, cognitive and behavioural.
Main types of symptoms
You may hear doctors or health care
professionals use the word ‘Chorea’ when
talking about Huntington’s disease. Chorea is
actually a Greek word, which means ‘dance’,
and it is used to refer to the irregular
movements people with Huntington’s disease
have. These movement symptoms often cause
people with Huntington’s disease to fall or drop
things a lot, look restless and appear ‘fidgety’.
In the early to middle stages of the disease
people can sometimes be mistaken for being
drunk, when in fact they have movement
symptoms. It is these movements that are probably the thing people notice most about
Huntington’s disease, and before doctors understood more about the other symptoms (like
those that affect the way we think), they used to call the condition Huntington’s Chorea.
Cognitive describes anything that requires ‘intellectual activity’ or our process of thinking,
basically anything that you have to put some thought into (like reading this page)! As the disease
progresses, people with Huntington’s disease may have difficulty keeping track of things,
making decisions or answering questions - that’s because the ability to concentrate becomes
more difficult for people with Huntington’s disease, as a result of their cognitive skills declining.
However, despite the loss of thinking ability, people with Huntington’s disease usually remain
able to understand and recognise others.
The condition can also affect people behaviourally, meaning that it affects the way people think
and the actions they take. Behavioural symptoms can cause people with Huntington’s disease
to feel depressed, anxious, lack energy, get angry easily or lose their temper over things that
don’t seem important. Sometimes people with Huntington’s disease behave inappropriately and
do or say things they don’t mean to (without thinking). These people are experiencing the
behavioural symptoms of Huntington’s disease and it is important to remember that when
someone with Huntington’s disease does something that upsets you or makes you mad - it is
most likely the Huntington’s disease causing them to behave this way.
Everyone is different
Although Huntington’s disease can affect movements, cognitive function and cause behavioural
symptoms, each person is impacted individually and it is impossible to predict how each person
will be affected. For example, one person with Huntington’s disease may have severe
involuntary movements (chorea), but very few behavioural symptoms. Another person with the
condition may have a lot of behavioural symptoms but only slight movements. Even two people
from the same family, who are both affected by Huntington’s disease, may have completely
different symptoms of the same disease.
Age
Symptoms of Huntington’s disease can begin
at any age; but most people with Huntington’s
disease usually develop symptoms between 30
and 50 years of age. Huntington’s disease is
caused by damage to the brain, particularly an
area of the brain called the ‘basal ganglia’. The
brain cells deteriorate over a long period of
time, usually 15-20 years, and during this time
the affected person slowly loses their abilities,
such as walking, talking and eating. This
happens gradually and the person with
Huntington’s disease can remain reasonably
well for some time - even after being diagnosed with symptoms.
The figures
Worldwide roughly one person in every eight thousand is affected by Huntington’s disease - so
it is quite a rare disease. But some places have more cases of Huntington’s disease than others.
For example, the condition is common in places like Europe or North America and it’s also
extremely common in a certain area of Venezuela. But the condition is thought to be far less
common in places such as Asia and Africa, although not enough research has been done on
these two continents to know exactly how many people are affected there. Huntington’s is often
referred to as a ‘family disease’ because of the affect it can have on the entire family and the
fact the disease is hereditary - so the condition impacts on far more lives than the figures
suggest.
Treatments
There is no cure or effective treatment which will slow down the progression of Huntington’s
disease yet. But there are treatments that can help control some of the symptoms and there is a
lot of research being done at the moment so there is great hope for the future! Visit our research
section to find out more about advances in research. We hope this website has helped
understand Huntington’s disease - however it affects you.
Hopefully this introduction to HD has helped. For more detailed information on HD and how it
impacts on young people, check out the rest of HDYO’s content.
This document was downloaded from the HDYO website at https://en.hdyo.org/eve/articles/57
Advice received via the HDYO web site should not be relied upon for personal, medical, legal or financial
decisions and you should consult an appropriate professional for specific advice tailored to your situation.
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