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Hugh's MD1 Neuro > Huntington's and Others > Flashcards

Flashcards in Huntington's and Others Deck (20):
1

What is the pathogenesis of Huntington's?

Expanded CAG repeated in hungtingtin protein that is toxic to basal ganglia cells > atropy eventually effects the whole brain

2

What are the genetics for Friedreich ataxia?

Autosomal recessive

3

How many repeats do you need to have to transmit Huntington's to offspring?

27-35

4

What is the mean age of onset for Huntington's?

35-44years

 

4

Where are the pathological effects of Huntington's seen?

The basal ganglia, particularly the striatum

 

4

What happens at the biochemical level in Friedreich ataxia?

The frataxin protein isn't produced.

Causing iron accumulation in mitochondria causing oxidative damage

5

What test is used for diagnosing Huntington's?

PCR - fragment analysis

6

What are the symptoms of Huntington's?

Movement disorder

Cognitive disorder

Emotional disorder

6

Which type of Spinocerebellar ataxia is most prevalent in Australia?

SCA3 (aka Machado-Joseph disease)

7

What is the usual cause of death in Friedreich ataxia?

Cardiomyopathy 

9

How can the repeats effect the protein/RNA/DNA?

1. Cause loss of protein

2. Cause novel properties to RNA

3. Cause novel properties to protein

 

11

What are the genetics of Huntington's and Spinocerebellar ataxia?

Autosomal dominant

12

How many bases are usually contained in the repeats?

3

14

How many repeats must you have for Huntington's to present?

>= 40

15

What does anticipation refer to in the context of Huntington's?

The more repeat sequences the more severe the disease is and the early the onset is.

16

T/F Just the basal ganglia are effected in a Huntington's brain

False, eventually the whole brain is atropied

17

What effect do the repeats have at the protein level in Huntington's?

Confers novel properties to the protein

18

What are some characteristics of neurodegenerative diseases caused by repeat expansions?

Loss of movement control

Variable and overlapping clinical presentation

Late onset

Symptoms worsen over time

DNA testing can aid diagnosis

19

What is the possible mechanism for insertion of repeats called?

Slipped mispairing

20

T/F Repeat regions are always abnormal.

False, they are present normally too