My young child has recently been diagnosed with a genetic condition putting him at strong risk for MODY5. I have had type 1 for 16 years. If he were to get it, would it strictly a result of his genetic condition or would he have inherited it from me? If that were the case, could I actually have MODY? I am ketosis prone, non-obese, very insulin sensitive, and my pancreas has atrophy, although not to the point of requiring digestive enzymes. Are MODY 5 patients usually treated with insulin?

Thanks for your question about MODY and MODY5. There are actually several kinds of MODY – single gene causes of diabetes. Our website describes them and shows how you can sign up for our registry. This is so we can learn more about the best way to diagnose and treat these important kinds of diabetes that affect about 300,000 to 400,000 people in the United States.

MODY5 is about the fourth most common form, so it is relatively rare. All the MODYs are very different from type 1 diabetes, which is an autoimmune disease, often associated with specific antibodies that are not present in MODY. MODY5 is caused by a mutation or a genetic loss of information – a deletion – encoding the gene for MODY 5 that is called HNF1B. It was discovered by my colleagues here at the University of Chicago almost 20 years ago. It is most often inherited but, of course, it has to start somewhere, so some people with MODY do not have parents with diabetes. When there is a parent with diabetes, they should also be tested for the same gene. So, yes, we should re-think what kind of diabetes you have and review what tests have been done and could still be done.

Now, in your question, you say something very interesting: “recently been diagnosed with a genetic condition putting him at strong risk for MODY5.� It may be that he has already has had genetic testing, but MODY5 is only diagnosed by genetic testing – either people have a mutation or deletion that causes it or they don�t. We are unaware of any partial effects. It may be that since he is young, he has not been diagnosed with diabetes yet – that can happen before the age of 25 – and there are some mutations in HNF1B that are associated with kidney problems more than diabetes, but both can happen.

A small pancreas can be the result of some MODY mutations, we are finding out – but the details are important. Some MODY patients are indeed treated with insulin, but we have not had the opportunity yet to explore many of the newer drugs that are used in type 2 diabetes. Some of them are very likely to help treat MODY diabetes. Sulfonylurea drugs such as glyburide are particularly effective in MODY3, for example.

Your questions are all excellent and we would be happy to be directly in touch with you and your son�s doctors to be sure we have as much information as possible to answer the questions in more detail, and perhaps to suggest additional tests that might be very helpful. I hope this answer was helpful and we look forward to being in touch directly.

LP