Huntington`s Disease (HD)
Description
Huntington‘s disease (HD) is a rare, inherited neurological disorder that causes progressive degeneration of nerve cells in the brain. This degeneration leads to a wide range of symptoms, including physical, cognitive, and behavioral changes. Although there is no cure for HD, there are treatments available to manage symptoms and improve quality of life.
Genes Involved
HD is caused by a mutation in the HTT gene, which is located on chromosome 4. This gene provides instructions for making a protein called huntingtin. The mutation in the HTT gene causes a protein with an abnormally long chain of glutamine. This abnormal protein accumulates in the brain cells and disrupts their function.
Recognizing the Signs and Symptoms
The signs and symptoms of HD typically appear in adulthood, often between the ages of 30 and 50. The disease progresses gradually, and the severity of symptoms can vary from person to person. Some common symptoms include:
- Movement disorders: Uncontrolled movements, such as jerking, twitching, or writhing, are often the first noticeable symptom. These movements are called chorea.
- Cognitive decline: This includes problems with memory, attention, planning, and decision-making.
- Emotional changes: People with HD may experience mood swings, irritability, depression, anxiety, or personality changes.
- Behavioral problems: These can include aggression, impulsivity, and social withdrawal.
Causes
Huntington‘s disease is caused by a genetic mutation. This mutation is inherited from a parent who carries the mutated gene. A person with HD has a 50% chance of passing the mutation on to each of their children.
Inheritance/recurrence risk
HD is an autosomal dominant disorder, meaning that if one parent has the mutated gene, there is a 50% chance that each child will inherit the mutation. If a person inherits the mutated gene, they will develop the disease. If they do not inherit the mutated gene, they will not develop the disease.
