Huntington's disease is an inherited disorder that results in death of brain cells. HD was described in further detail in 1872 by George Huntington, after whom it is named
Genetic process. The disease is caused by an autosomal dominant mutation. Huntingtin gene provides the genetic information for a protein that is also called "huntingtin".
All
humans have two copies of the Huntingtin gene (HTT), which codes for the
protein Huntingtin (HTT). The mutation in the gene coding for the Huntingtin
protein results in an abnormal protein.The
differing functions of these proteins are the cause of pathological changes which in turn cause the disease symptoms.
The Huntington's
disease mutation is genetically dominant
and almost fully penetrant: mutation of either of a person's HTT alleles causes
the disease. It is not inherited
according to sex.
Symptoms of
Huntington's disease most commonly become noticeable between the ages of 35 and
44 years, but they can begin at any age from infancy to old age.
· In the early stages,
there are subtle changes in personality,
cognition, and physical skills.
The physical symptoms are usually the first to be noticed, as cognitive and behavioral symptoms.
The physical symptoms are usually the first to be noticed, as cognitive and behavioral symptoms.
· The most
characteristic initial physical symptoms are jerky, random, and uncontrollable movements.
· Chorea may be initially exhibited as general restlessness, small
unintentionally initiated or uncompleted motions, lack of coordination, or
slowed saccadic eye movements.
·
The clear appearance
of symptoms such as rigidity,
writhing motions or abnormal posturing
appear as the disorder progresses.These are signs that the system in the brain
that is responsible for movement has been affected.
· Psychomotor functions become increasingly impaired, such that any action
that requires muscle control is affected.
· Cognitive abilities are progressively impaired. Especially affected
are executive functions, which include planning, cognitive flexibility,
abstract thinking, rule acquisition, initiation of appropriate actions, and
inhibition of inappropriate actions.
· Cognitive problems
tend to worsen over time, ultimately leading to dementia.
· Reported
neuropsychiatric manifestations are anxiety,
depression, a reduced display of emotions (blunted affect), egocentrism,
aggression, and compulsive behaviour…
· Complications such as pneumonia, heart disease, and physical injury from falls reduce
life expectancy.
· Death
typically occurs fifteen to twenty years from when the disease was first
detected.
Diagnosis is by genetic testing, which can be
carried out at any time, regardless of whether or not symptoms are present.
Treatment. There is no cure for HD. Treatments can
relieve some symptoms and in some improve quality of life.
Future. Current research directions include
determining the exact mechanism of the disease, improving animal models to aid
with research, testing of medications to treat symptoms or slow the progression
of the disease, and studying procedures such as stem cell therapy with the goal
of repairing damage caused by the disease.
Webpage:
https://ca.wikipedia.org/wiki/George_Huntington
https://ghr.nlm.nih.gov/condition/huntington-disease
https://www.huntingtonsociety.ca/learn-about-hd/what-is-huntingtons/
http://huntingtonsqld.org.au/huntingtons-disease/what-is-hd/
Webpage:
https://ca.wikipedia.org/wiki/George_Huntington
https://ghr.nlm.nih.gov/condition/huntington-disease
https://www.huntingtonsociety.ca/learn-about-hd/what-is-huntingtons/
http://huntingtonsqld.org.au/huntingtons-disease/what-is-hd/
