Huntington's Disease

Every child of a parent with HD has a 50/50 chance of inheriting it, so it is ultimately a family disease.
It is caused by a fault in the gene that instructs the formation of a protein called huntingtin. We all inherit two copies of every gene – one from each of our parents. If the child of an HD parent inherits the faulty gene they will subsequently develop the disease at some time in their life. If the child of an HD parent inherits the gene that isn’t faulty they will never develop the disease and will not pass the disease to any of their offspring.

HD affects between 5 and 10 people per 100,000 inhabitants in Europe and in other countries with populations that are primarily of European descent. HD is less common in Asia and Africa.
Males and females are equally affected.
In Switzerland there are approximately 400 people with HD.

Malfunction in huntingtin production damages nerve cells in specific areas of the brain.
A combination of physical, behavioural and cognitive changes can occur together or at different stages. Symptoms vary in type, severity and rate of progression from one person to another, and even from one family member to another.

Physical changes include jerky movements, loss of balance, difficulty speaking and swallowing.
Common behavioural changes include apathy, anxiety, depression, irritability, anger, impulsiveness, obsessive-compulsive behaviour, sleep disturbances and withdrawal.
Cognitive problems include the gradual impairment of comprehension, reasoning, judgement and memory.
Other symptoms can include loss of appetite and weight, loss of self-esteem, loss of sex drive, and urinary and faecal incontinence.
The age of onset is usually between 30 and 50 but subtle shifts in mood, mental ability, coordination and gait may go unnoticed until the disease progresses.

HD is diagnosed through a combination of clinical assessments and genetic testing. Clinical diagnosis is based on a person’s medical and family history as well as standard examinations that make use of clinical rating scales to assess the frequency and severity of symptoms. The results of the clinical diagnosis are usually confirmed by genetic testing.

There is currently no cure for HD, but in recent years there has been a dramatic and promising increase in studies aimed at understanding and treating the underlying cause.
In the absence of a cure, available treatment focuses on alleviating symptoms and improving the quality of life.

It’s a particularly exciting time for HD research. Doctors and scientists all around the world are actively engaged in countless research projects and clinical trials in the field of neurology in general, and HD in particular.
Through membership of both the European Huntington’s Association (EHA) and International Huntington’s Association (IHA) the SHV maintains close links to the global HD community and keeps up to date with the latest research and clinical trial developments.

Living with the knowledge that you are at risk of HD can be very worrying. You may feel that you would prefer to know for certain if you are affected, or you may be confused about whether or not you want to know. Either way, genetic and psychological counselling is invaluable. The outcome of predictive testing has a significant impact, for which you need to be fully prepared. If you choose to get tested, or if you want to explore the option further, your doctor will refer you to a genetic counsellor. Only after counselling and confirmation that you still wish to know your HD status, is a sample of blood taken so that your DNA can be analysed.
It is not recommended for those under 18.