HUNTINGTON’S DISEASE

M A G G I E

P H O E B E L E O N O R A

B Y :

NAME OF DISORDER? ARE THERE OTHER NAMES FOR DISORDER/DISEASE (WHAT ARE THEY)?

Huntington's disease

-first described the disorder in 1872 by American doctor George Huntington

-Also known as Huntington's chorea

-Two forms:

1) most common

-adult-onset Huntington's disease

-get symptoms in mid 30s & 40s

2) early-onset Huntington's disease

-not many people have it

-similar symptoms to Parkinson's disease (slow movements & tremor)

HOW IS THIS DISORDER/CONDITION INHERITED? (EX: X-LINKED, NONDISJUNCTION, AUTOSOMAL

RECESSIVE, AUTOSOMAL DOMINANT, ETC.)

-Progressive, degenerative disease that causes certain nerve cells in brain to waste away and is passed down through families

-Genetic defect is on chromosome #4, this causes this part of DNA to repeat 10 to 35 times in a normal person while its 26 to 120 in a person with Huntington's disease

- One parent has Huntington's disease= 50% chance of getting the gene

-If you have the disease it will mean a parent had it, if you have it your kids will, if not there is no way they can

CAN SOMEONE BE A CARRIER FOR THE DISORDER/CONDITION?

-Huntington’s disease is a rare fatal brain disease caused by inherited changes in only one gene

-these changes lead to destruction of nerve cells in certain places in the brain

-Scientists identified the gene in 1993, which is gene #4

-anyone with a parent with Huntington’s has a 50 percent chance of inheriting the gene, and everyone who inherits it will eventually have the disorder

-The defect causes a part the DNA pattern, called a CAG to repeat, to occur many more times than it is supposed to occur

-usually this section of DNA is repeated 10 to 35 times, but for people with Huntington's disease, it is repeated 36 to 120 times

WHAT IS THE FREQUENCY OF THE DISORDER/CONDITION?

-The frequency of HD in different countries varies greatly

-Few isolated populations of western European origin have higher prevalence of HD that shows to be from a founder effect

-Including: Lake Maracaibo region in Venezuela (700 per 100,000 people), the island of Mauritius off the South African coast (46 per 100,000 people), and Tasmania (17.4 per 100,000 people)

-The prevalence in most European countries ranges from 1.63-9.95 per 100,000 people

-Everyone is affected differently based on the way their brain goes through development

WHAT ARE THE SYMPTOMS/EFFECTS & PROGNOSIS OF SOMEONE WITH THIS DISORDER? -The earliest symptoms and most common are usually related to mood and

result in slight personality changes.

-seem more eager

-may not actually have clinical symptoms

-irritability

-Middle Age Symptoms:

-muscle spasms, uncontrollable movement, change in speech is more obvious, trouble swallowing.

-Three Categories:

-motor or movement symptoms

-personality and behavioral changes

-cognitive decline

-(Severity can vary from person to person)

HOW IS THE DISORDER/DISEASE DIAGNOSED?

-Look at family medical history

-An inherited disease

-Magnetic resonance imaging (MRI) or computed tomography scan (CT scan)

-genetic test: small blood sample- analyzed to determine the CAG repeat #

-Linkage test- examines the pattern of DNA near the gene in both parents and fetus

WHAT IS THE TREATMENT, IF ANY?

-No treatment

-Doctors treat with medication that slows the progression of disease

-These medicines treat symptoms & speed of progression

-Anti-seizure medication= ease uncontrollable movement

-Tranquilizers= alleviate outbursts & calm patient

-There are some side effects: over-excitability to extreme fatigue & restlessness

-Subside over time, if sever they use new combos

-Scientists have bread lab animals implanted with fetal tissue to try to promote regeneration

-Researchers have also tried various chemical compounds that may stimulate brain to overcome HD's degenerative effects

IS THERE A CURE? IF SO, WHAT IS IT? IF NOT, WHAT PROGRESS ARE SCIENTISTS MAKING

TOWARD FINDING A CURE?

-Currently no cure for Huntington’s

-Research on potential treatments is increasing since scientists identified the gene that causes the disorder

-In 2008, the U.S. Food and Drug Administration (FDA) approved tetrabenazine (Xenazine™) as the first drug specifically approved in the United States to treat the disorder movements associated with Huntington’s

-Doctors also sometimes prescribe other drugs to manage symptoms

THE END

WORKS CONSULTED

Dugale III, David C. Huntington’s Disease. 6/24/09. http://www.healthline.com. 1/28/11

Gale, Thomson. Huntington’s Disease. The Gale Encyclopedia of Neurological Disorders. Stacey L. Chamberlin, Brigham Narins. Farmington Hills. Thomson Gale, in 2005. Volume 1. 1/26/11.

Knowles, Johanna. Huntington's Disease. New York: The Rosen Publishing Group Inc. , 2007. Print.

Lawrence, David M. Huntington’s Disease. Genes and Disease; Huntington’s Disease. New York. Chelsea House Publishing Group, in 1961. 1/26/11.

Robinson, Richard. "Huntington's disease." The Gale Encyclopedia of Medicine. Detroit: Gale, 1999. 1489. Gale Science In Context. Web. 28 Jan. 2011.