Monogenic Diabetes

Question 1

If a parent has diabetes, risk of one having diabetes is …

If both parents have diabetes, risk of one having diabetes is …

Answer 1

40%
80%

Question 2

Fat storage threshold

Answer 2

Insulin resistance occurs when fat can no longer be safely stored in s/c adipose tissue causing spill over of FFA to the viscera. People with ‘healthy’ obesity are able to safely store lots of fat; others have low fat storage threshold

Question 3

What is insulin resistance associated with other than DM?

Answer 3

Hypertension
Hyperlipidaemia
Hyperglycaemia – even in absence of diabetes
Polycystic Ovarian Syndrome (in women)

Hence it is necessary to control lipids and blood pressure in diabetes as well

Question 4

What do most monogenic diabetes have defect in?

Answer 4

Defects in insulin secretion (beta cells)
eg. Maturity Onset Diabetes of the Young
Neonatal diabetes

Question 5

What are features of severe insulin resistance?

Question 6

What are some monogenic insulin resistance conditions where there are defects in fat storage?

Question 7

What is MODY?

Answer 7

Autosomal dominant inheritance

Non-insulin dependent diabetes

Age of onset usually before age 25

Question 8

If someone has glucokinase mutations, how would their insulin secretion in response to glucose be different?

Answer 8

Question 9

How do MODY patients with glucokinase mutations and transcription factor mutations present differently?

Answer 9

Question 10

Why is sulphonylurea a useful drug for KCNJ11 MODY? (a gene in K+ channels)