Term
| average age of onset of Huntington's disease? |
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Definition
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Term
| T or F - the gene frequency of Huntington's is 2.5- 3 times higher than the actual prevalence of Huntignton's due to the fact that 2/3 of gene carriers have yet to develop symptoms |
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Definition
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Term
| what is the average duration of Huntington's disease? |
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Definition
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Term
| what percentage of cases is juvenile onset? |
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Definition
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Term
| what is the main triad of clinical features in Huntington's disease (HD)? |
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Definition
1. Movement disorder
2. Dementia
3. Psychiatric disorder |
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Term
| what is the most common cause of death for HD patients? |
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Definition
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Term
| involuntary, writhing movements that are often apparent in HD are called |
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Definition
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Term
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Definition
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Term
T or F
eye movement disorders are common in HD |
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Definition
| True - saccadic difficulties, difficulty tracking objects |
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Term
| name as many symptoms/clinical features of HD as you can |
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Definition
1. Chorea: involuntary, writhing movements
2. Other hyperkinetic movements: tics, myoclonus
3. Eye movement disorders:
4. Impaired fine motor coordination
5 Dysarthria (slurred speech) and dysphagia (trouble swallowing)
6. Gait difficulty
7. Less frequent: dystonia and parkinsonism
- Common in juvenile onset
- May be seen late in disease in adult onset |
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Term
T or F
Motor symptoms begin to occur in HD before cognitive impairment sets in. |
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Definition
| False - cognitive impairment often occurs prior to motor symptoms |
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Term
| Describe some of the cognitive impairments of HD |
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Definition
- impaired executive function (planning things, focusing)
- Impaired attention/concentration
- Deficits in recognizing facial emotion
- anosognosia - denial of extent of disease and lack of insight into own disease |
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Term
What percentage of HD patients have depression?
What percentage have psychosis? |
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Definition
40-60% depression
5-25% psychosis |
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Term
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Definition
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Term
| Juvenile onset HD is associated with high repeats of what nucleotide triplet sequence? |
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Definition
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Term
| juvenile HD is more associated with (paternal/maternal) inheritance |
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Definition
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Term
T or F
In juvenile HD, Chorea is common |
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Definition
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Term
Juvenile HD or Adult HD?
rigidity and akinesia |
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Definition
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|
Term
Juvenile HD or Adult HD?
Seizures common |
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Definition
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|
Term
Juvenile HD or Adult HD?
no cerebellar atrophy |
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Definition
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Term
Juvenile HD or Adult HD?
shorter CAG repeats |
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Definition
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Term
Juvenile HD or Adult HD
either paternal or maternal transmission |
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Definition
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Term
| what pathological brain characteristics are found in Juvenile HD? |
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Definition
- small brain (30% decrease)
- striatal atrophy
- cortical atrophy
- cerebellar atrophy |
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Term
| What part of the brain is involved in HD? |
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Definition
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Term
| What is the pathology in the striatum with HD? |
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Definition
| loss of spiny, GABAergic neurons |
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Term
| What is the pathology in the cortex with HD? |
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Definition
- loss of pyramidal neurons
- layers III, V, VI particularly affected |
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Term
| intranuclear inclusion bodies in surviving neurons in Huntington's stain for what proteins? |
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Definition
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Term
| the direct pathway of the basal ganglia (inhibits/promotes) movement |
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Definition
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Term
| the indirect pathway of the basal ganglia (inhibits/promotes) movement |
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Definition
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Term
| the direct pathway tends to promotes movement by inhibition of the output of what nucleus |
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Definition
|
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Term
| the indirect/direct pathway is most associated with HD? |
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Definition
|
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Term
| what type of genetic inheritance pattern does HD show? |
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Definition
|
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Term
| Huntington's is a disease caused by a mutation in what gene? |
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Definition
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Term
| ___ repeats on the huntingtin gene is representative of HD |
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Definition
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Term
| normal people usually have less than 29 CAG repeats on their huntingtin gene, while HD patients have more than ___ |
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Definition
|
|
Term
| what does the CAG triplet code for? |
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Definition
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Term
| number of CAG repeats is (directly/inversely) related to the age of onset and duration |
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Definition
| inversely - the more repeats you have, the younger you are when the disease develops, and the shorter it will last |
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Term
| anticipation in HD refers to what? What is the mechanism of this phenomenon? |
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Definition
| Later generations develop HD at earlier ages. CAG repeats are stable in most tissues except for sperm. During spermatogenesis, CAG repeats can become elongated. |
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Term
T or F
The function of huntington is unknown, but knockout of the gene is embryonic lethal |
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Definition
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Term
| So the cortical neuron helps to support the caudate neuron by providing a trophic factor called ____ |
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Definition
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Term
(Both blanks are same word)
astrocytes tend to sop up the ______ that’s released at the synapse of the cortical pyramidal neuron and if you have this hanging around too much it can cause what we call an excytotoxicity and lead to the activation of cell death pathways. And there’s a disruption of this ____ clearance of that helps promote the loss of this caudate neuron. |
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Definition
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Term
T or F
inflammatory responses do not contribute to cell death of medium spiny neurons in striatum in HD |
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Definition
| false - activated microglia release inflammatory mediators that contribute to cell death of medium spiny neurons in the striatum in HD |
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Term
| what's the definitive way to diagnose the disease? |
|
Definition
| test for CAG repeat expansion |
|
|
Term
| what is the consequence of a lesion to the left subthalamic nucleus? |
|
Definition
| right heminallismus - flinging movements |
|
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Term
| main treatment for chorea today is? |
|
Definition
| the dopamine depleter TETRABENAZINE |
|
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Term
| are cholinesterase inhibitors effective in HD associated dementia? |
|
Definition
|
|
Term
| what meds are used for HD associated psychosis? |
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Definition
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