Huntington Disease

Question 1

Which nucleotides are repeated in Huntington disease?

Answer 1

CAG

Question 2

Do non-affected individuals have CAG repeats?

Answer 2

yes, but only 8-39 instead of 36-121

Question 3

Genetic anticipation

Answer 3

might happen earlier in next generation

due to increased penetrance and more repeats

Question 4

NMDA receptor in HD

Answer 4

modifier gene: may affect degree of severity

Question 5

Which protein tags proteins to be destroyed?

Answer 5

ubiquitin

Question 6

Are HTT proteins tagged w/ ubiquitin?

Answer 6

yes but still not degraded

Question 7

Why is HD inherited more easily from affected fathers? And more genetic anticipation higher?

Answer 7

spermatogenesis is more instable

Question 8

<35 CAG repeats

Answer 8

normal

Question 9

36-41 CAG repeats

Answer 9

incomplete penetrance

Question 10

40-60 CAG repeats

Answer 10

full penetrance

Question 11

60+ CAG repeats

Answer 11

full penetrance, possible juvenile onset

Question 12

What type of neurons are loss in HD?

Answer 12

medium spiny neurons in basal ganglia

and some in cortex

Question 13

How many grades of HD are there?

Answer 13

5:
0-1: no gross atrophy
2: beginning atrophy
3: more atrophy
4: more severe, concave caudate

Question 14

Is there gliosis in HD?

Answer 14

yes

Question 15

Haloperidol mechanism

Answer 15

D2 antagonist

Question 16

Tetrabenazine mechanism

Answer 16

monoamine depleting agent by inhibiting their transport into presynaptic vesicles