MCBG

Question 1

What is Huntington’s disease?

Answer 1

• Mutation in HTT gene
• Gene contains 6-39 CAG repeats if normal – above 40 leads to Huntington’s.
• Mutant protein disrupts normal functions within neurons.
• Progressive brain disorder
• Symptoms can include irritability, depression, small involuntary movements, poor coordination.

Question 2

What is Werner’s syndrome?

Answer 2

• Mutation in the WNR gene that codes for a helicase that is important during DNA replication.
• Leads to premature ageing.

Question 3

Why do people develop scurvy?

Answer 3

Vitamin C deficiency

Enzyme needed for increased H-bonding between tropocollagen molecules to stabilise the triple helix requires vitamin C and Fe++ ions for activity - scurvy is due to weak tropocollagen triple helices