Understanding Diabetes

MODY (maturity onset diabetes of the young)

What is MODY?

MODY or ‘maturity onset diabetes of the young’ is a type of diabetes affecting young people. It runs in families and often develops before the age of 25 years.

What is the main defect in MODY?

The main problem relates to the production of insulin by the pancreas.

How common is it?

About 1-2% of people who have diabetes may have MODY.

How is it inherited?

This condition occurs due to inheriting a defective gene from one’s parents. It is Autosomal Dominant which means that just one of the parrents needs to have the condition in order  to pass it on.

What are the chances of inheriting it?

If one of the parents has MODY the children will have a 50% chance of inheriting the gene and therfore developing MODY. In other words each child has a 50-50 chance of developing the condition. It is important to recognise that this is a ‘statistical’ estimate of risk. You could have six children and all of them could still be affected and it is equally possible that none are affected.

What are the different types of MODY?

There are 5 genes which have been identified as causing MODY. The type of MODY inherited will depend on the gene responsible and are labelled as MODY 1 to MODY 5.

The 5 genes identified are:

  • HNF1-a
  • Glucokinase
  • HNF1-b
  • HNF4-a
  • IPF1

Why is it useful to recognize MODY?

  • To decide on appropriate treatment.
  • Knowing the type of MODY will help predict how diabetes is going to progress.
  • To advise other family members on risk of inheriting the condition and passing it on.

How is MODY treated?

Just like type 2 diabetes  with diet and exercise. Sometimes, tablets or insulin are required.


Dr Nishan Wijenaike, Consultant Physician
West Suffolk Diabetes Service
August 2003