Huntingtons Disease

Question 1

How does huntingtons manifest?

Answer 1

1) Movement
- bradykinesia
- dystonia (spasms)
- chorea (jerky movements)

2) Mood
- depression
- euphoria
- anxiety
- agression

3) Cognition
- loss of executive functioning.

Question 2

How is HD inherited?

Answer 2

Autosomal dominant

Question 3

What gene is affected in HD?

Answer 3

The huntingtons gene at 4q16.3 has over 40 CAG repeats.

Question 4

What is anticipation?

Answer 4

The onset of a disease gets earlier as its passed on from one gen to the next. Also the severity of symptoms increases.

Question 5

Anticipation is associated with triplet repeat disorders. Name some of them

Answer 5

1) huntingtons
2) myotonic dystrophy
3) fragile X syndrome

Question 6

Huntingtons, myotonic dystrophy and Fragile X syndrome are triplet repeat disorders - how are the inherited?

Answer 6

1) Huntingtons = autosommal dominant
2) Myotonis dystrophy = autosomal dominant
3) Fragil X syndrome = X-linked recessive.

Question 7

Predictive testing is used in an asymptomatic person to predict future risk of disease. What disease is predictive testing possible?

Answer 7

1) huntingtons
2) BRCA (familial breast cancer genes)
3) HNPCC (hereditary non-polyposis colon cancer)
4) Myotonic dystrophy