If you have diabetes, you’ll probably be familiar with type 1 and type 2. What you may not realise is that there are other, much less common forms too. Some rare types of diabetes can look very similar to the more familiar types, which sometimes makes them difficult to spot. MODY diabetes and LADA diabetes are two examples. They develop for different reasons, and getting the right diagnosis can affect your treatment, monitoring and even whether other members of your family should be tested.
What is MODY diabetes?
MODY stands for maturity onset diabetes of the young. It is a type of monogenic diabetes, which means it’s caused by a change in a single gene. That makes it different from type 1 and type 2 diabetes. Type 1 is caused by an autoimmune reaction, while type 2 usually develops through a mixture of genetic and lifestyle related factors.
If you have MODY diabetes, there’s often a noticeable history of diabetes in your family. Several generations may have been diagnosed, sometimes at a relatively young age. If one of your parents has the gene change responsible for MODY, you have a 50% chance of inheriting it.
According to Diabetes UK guidance on MODY, MODY may account for around 1 to 2% of diabetes cases in the UK. Some people are initially told they have type 1 or type 2 diabetes instead.
Are there different types of MODY?
There is not just one form of MODY diabetes. Different gene changes cause different types, and the effect on your blood glucose can vary considerably. HNF1A MODY is one of the more common forms. It often appears in adolescence or early adulthood, and some people can manage it with low-dose sulphonylurea tablets rather than insulin. HNF4A MODY is similar in some respects. It can also be associated with a high birth weight or low blood glucose shortly after birth.
GCK MODY tends to cause a mild, stable rise in blood glucose. If you have this type, you may only discover it after having routine blood tests. Treatment is not always needed outside pregnancy. HNF1B MODY can also affect your kidneys and other organs, and you may need insulin.
How would you know if you have MODY?
You cannot tell whether you have MODY simply from your symptoms. Your doctor may start to consider it if your diabetes was diagnosed when you were young, if it runs through several generations of your family, or if your condition doesn’t behave as expected. You can have blood tests to look for pancreatic autoantibodies. A C-peptide test can also help show whether your pancreas is still making its own insulin.
If MODY is suspected, genetic testing can confirm whether a relevant gene change is present. The NHS Genomics Education Programme explains how genetic testing can help guide treatment and provide useful information for relatives. For you, getting the correct diagnosis could mean changing treatment. It may also mean that close family members are offered testing.
What is LADA diabetes?
LADA stands for latent autoimmune diabetes in adults. Although it is sometimes confused with type 2 diabetes, its underlying cause is different. If you have LADA diabetes, your immune system attacks the beta cells in your pancreas that make insulin. This is similar to what happens in type 1 diabetes. The difference is the speed at which things happen. LADA usually progresses more slowly, so you may still produce enough insulin at first to manage without insulin injections. Because of this, you may initially be diagnosed with type 2 diabetes, particularly if you develop symptoms as an adult.
You may also hear LADA described as “type 1.5 diabetes”. This informal term reflects the fact that it shares features with both type 1 and type 2. Diabetes UK information on LADA explains the condition in more detail.
How is LADA different from type 2 diabetes?
If you have LADA diabetes, your symptoms may be very similar to those of other types of diabetes. You might feel unusually thirsty, need to urinate more often, feel tired or lose weight without trying. One important difference is the autoimmune process. Blood tests can look for diabetes-related autoantibodies, such as GAD antibodies, which may help your healthcare team work out whether LADA is the more likely diagnosis. Over time, your pancreas will make less insulin. This means you may need insulin treatment sooner than somebody with typical type 2 diabetes.
Why does getting the right diagnosis matter?
Knowing which type of diabetes you have can make a real difference to your care. With MODY diabetes, your treatment may depend on the particular gene involved. Some people need insulin, some respond well to tablets and others may not need glucose-lowering medication at all.
With LADA diabetes, recognising that your insulin production is gradually declining can help you and your diabetes team plan ahead. If you feel your diagnosis does not quite fit your age, family history or response to treatment, speak to your GP or diabetes team. Do not stop or change any medication yourself. Rare types of diabetes need specialist tests before a diagnosis can be confirmed.
FAQs
Can MODY be mistaken for type 1 diabetes?
Yes, MODY is sometimes mistaken for type 1 diabetes. If you develop diabetes while you are young, MODY diabetes can sometimes look like type 1. Your doctor may investigate further if several generations of your family have diabetes, you are still producing your own insulin or tests for pancreatic autoantibodies are negative. Genetic testing is normally needed before MODY can be confirmed.
Can you inherit MODY or LADA?
MODY diabetes has a strong genetic link. In many forms, if one of your parents carries the gene change, you have a 50% chance of inheriting it. LADA diabetes is different. Your genes can influence your risk of autoimmune diabetes, but LADA is not passed from parent to child in the same straightforward single gene pattern.
