Not in the mood for MODY

Diabetes is a disease characterised by high blood sugar levels which can result in long term complications related to the heart, brain, kidney, eyes and feet, if left uncontrolled.

There are various types of diabetes, the most common of which is Type 2 Diabetes. Type 1 and Type 2 Diabetes are of polygenic origin, meaning they are related to changes or defects in multiple genes as well as other factors like the environment, which can play a role in its manifestation. Thus, generally, diabetes results from multiple factors, of which defects in insulin hormone is the most important. In Type 1 Diabetes, the beta cells of the pancreas are extensively damaged and hence unable to produce insulin. This type of diabetes occurs typically in the first decade of life or early second decade of life. Such patients need insulin injections to control their sugars. In Type 2 Diabetes, the beta cells of the pancreas are functioning but not able to produce enough insulin to meet the demands of the body. This could be either due to a genetic problem, or multiple defects in various organ systems of the body. One such subtype of type 2 diabetes is what is called ‘MODY’ or Maturity Onset Diabetes of the Young.

MODY is typically a monogenic form of diabetes and is a result of mutations or changes in a single gene. It accounts for 1-4 % of all diabetes case. This is a rare form of diabetes, and the gene mutation is inherited from one or both parents. Sometimes the mutation develops spontaneously, meaning that the mutation is not carried by either of the parents. Mutations are abnormalities or defects in the genetic material, passed on by one generation to next, which affect the normal functioning of the genes, resulting in reduced production of hormones and peptides, which are vital to sustain normal bodily functions.

In MODY, the mutations result in decreased production of insulin as the genes providing instructions for making proteins within the cells do not function properly. Insulin is the hormone which is required for keeping the blood sugar levels under control. It is important to recognise and diagnose MODY as the behaviour of diabetes is different from the most common Type 2 Diabetes. The onset of MODY is usually during adolescence or early adulthood. The clinical features depend on the gene mutation a person has.

Symptoms may be mild to moderate, and some patients will not develop any long-term complications. However, some types of MODY require specific treatment with either insulin or sulphonylureas. Typically, family history of diabetes in multiple successive generations will be present. The diagnosis of MODY can be confirmed by genetic testing. An endocrinologist will suggest the appropriate genetic testing. A proper diagnosis means better long-term treatment planning as well as mapping the prognosis. 

Restrictions similar to Type 2 Diabetes apply for these patients. Dietary modifications with the right balance of carbohydrates, proteins and fat with the right mix of greens and dairy products would be suggested for these patients. Lifestyle modifications will be essential, although considering that the problem is more of a genetic defect it may have limited implications. Home management is as for most Type 2 Diabetes patients, but close monitoring for those on multiple tablets and insulin injections would help in achieving better control of sugars.

(The author is a consultant endocrinologist.)