Download Huntington*s Disease


Only caused by:
› Inherited genetic defect
› Mutation
Defect or mutation is a CAG repeat in
the HD gene of chromosome 4
 CAG repeat  abnormal Huntingtin
protein synthesized
 Abnormal Huntingtin protein leads to
premature death of nerve cells


Nervous System
› Emotional
› Physical

Immune System
Digestive System
 Accidents
 Death

Stubbornness and frustration
 Mood swings/changes

› Unorganized
› Difficulty concentrating
› Loss of motivation
› Loss of ability to interact
Perceived laziness puts stress on
relationships
 Depression


Premature death of nerve cells
› Loss of short-term memory
› Clumsiness
› Stumbling
› Difficulty walking

Uncontrollable muscle movements
› Difficulty with speech
› Difficulty swallowing
› Less able to sit/stand stably

Uncontrollable muscle movements lead
to difficulty swallowing
› Weight loss and lack of nutrients as a result
 Weakened immune system
PRONE TO INFECTION

Difficulty swallowing from uncontrollable
muscle movements
› Weight loss
› Lack of nutrients
› Choking

Uncontrollable muscle movements lead
to:
› Falling
› Self-injury
› Unable to take care of oneself
Depression may lead to suicide
 Death can also be cause by:

› Falling
› Infection
› Self-injury
› Choking
** Falling and infection are the most common
causes of death in Huntington’s Disease.
Huntington’s disease is incurable, but you
can treat some symptoms.
 Medication
› Movement
› Mental

Therapy
›
›
›
›
Speech
Physical
Psycho
Occupational

Movement disorders
› Tetrabenazine
 Help suppress involuntary movement
› Antipsychotic drugs (Haldol &Clozaril)
 Side effect of suppressing movements

Psychiatric disorders
› Antidepressants (Lexapro, Prozac, Sarafem, &
Zoloft)
› Antipsychotic drugs
 Suppress violent outbursts
› Mood-stabilizing drugs
 Prevent highs and lows associated with bipolar disorder

Psychotherapy
› Talk therapy to help with behavioral issues
and learn coping mechanisms

Physical therapy
› Help strength, flexibility, balance and
coordination to reduce falls

Speech therapy
› Strengthen muscles associated with speech,
swallowing, and eating

# of CAG repeats on
chromosome 4
› 11-34 = Normal
› 37-121 = Huntington’s Disease

Too many repeats lead to production of
abnormal Huntingtin protein
› Function of Huntingtin protein not known yet
› But function does affect basal ganglia

Basal ganglia
› Control over movement of body

GABA neurons in basal
ganglia
› Produce GABA neurotrans-
mitters (inhibitors)
 Stop some “messages”
from travelling through basal ganglia

Huntington’s Disease
GABA function
› Putamen's inhibitory GABA neurons are
destroyed
› Lead to disinhibition of thalamus and brainstem
› Disinhibition = random, frequent motion

Putamen
› Part of basal ganglia
› Helps control movement of body
 Projection to SNpc (substantia nigra pars
compacta) is necessary for movement

Huntington’s Disease
Putamen
› Projection to SNpc
destroyed due to
abnormal Huntingtin
protein
› Increased firing of
dopamine neurons
› Leads to disinhibition of
thalamus and
brainstem
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"Effects of Huntington's Disease." What Are the Effects of Huntingtons Disease? Neurological Physiotherapy & Rehabilitation Physiotherapists.
Manchester Neuro Physio. Web. 06 June 2012. <http://www.manchesterneurophysio.co.uk/huntingtons/effects.html>.
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<http://www.macalester.edu/psychology/whathap/UBNRP/Huntington/neuro.html>.
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<http://www.mdvu.org/library/disease/hd/hd_path.asp>.
Nordqvist, Christian. "What Is Huntington's Disease? What Causes Huntington's Disease?" Medical News Today. MediLexicon International, 02 Aug. 2009.
Web. 06 June 2012. <http://www.medicalnewstoday.com/articles/159552.php>.
Staff, Mayo Clinic. "Definition." Mayo Clinic. Mayo Foundation for Medical Education and Research, 05 May 2011. Web. 06 June 2012.
<http://www.mayoclinic.com/health/huntingtons-disease/ds00401/dsection=treatments-and-drugs>.
"Huntington Disease." Huntington Disease. WebMD. Web. 06 June 2012. <http://emedicine.medscape.com/article/1150165-overview>.
In which chromosome does the
Huntington’s Disease causing CAG
repeat occur?
 What are the most common causes of
death in Huntington’s Disease?
 What are three types of therapy
effective in treating Huntington’s
Disease?
