Genetics of MODY: Inheritance, Genes, Symptoms and Treatment

MODY, or maturity onset diabetes of the young, usually affects children and younger adults, and is caused by a genetic defect. Initially, it can mimic type 1 diabetes, however, it is often treatable with diet changes. Only a small subgroup of type 2 diabetics will develop this disease and of the people in this subgroup, they tend to have several family members with diabetes, and they are typically not obese as some type 2 diabetics are. Less than five percent of type 2 diabetics have MODY.

MODY Classification

In order for a patient to be diagnosed with maturity onset diabetes of the young, they must:

• Have type 2 diabetes and not type 1 diabetes.
• Have diabetes that does not need insulin to be controlled for a minimum of two years. Instead, patients will be able to control their diabetes through diabetes medications and/or through exercise and diet.
• The age of onset for a minimum of one family member has to be younger than 25 years of age.

MODY Mode of Inheritance

Part of understanding MODY is understanding the genetics of MODY. This disease is developed through inheriting a specific gene that will predispose them to this disease. Patients only need to inherit a mutated version of the gene that can cause MODY from one of their parents to be at risk. This condition has an autosomal dominant inheritance pattern. So, if just one parent has this condition, their children will have a 50 percent chance of inheriting the gene that increases their risk of developing MODY.

Genes Associated with MODY

As of today, five genes have been identified that can increase a person’s chance of developing this condition. All five of these genes interferes with the pancreas’ normal insulin release. However, of the five identified genes, only three are understood well. These three genes include HNF-4alpha, HNF-1alpha, and GCK.

Signs and Symptoms of MODY

Since this disease affects the body similar to how other types of diabetes do, the symptoms are also similar. These symptoms can include excessive thirst, gum disease, frequent urination, persistent skin infections and yeast infections, fatigue, and unexplained weight loss.

How is MODY Treated?

In most cases, MODY is treated in the same fashion as type 2 diabetes in treated. Most patients control this disease by testing their blood sugar regularly, and with diet and exercise. In some cases, patients may need to take oral diabetes medications, and in even less common cases, insulin injections may be necessary. Many patients will use a combination of treatments to best control their symptoms.

Resources

Adams, A. (2000). Genes Can Cause MODY. Retrieved on June 19, 2010 from Genetic Health: https://www.genetichealth.com/DBTS_Genetics_of_MODY.shtml

Diabetes Monitor. (2010). Maturity Onset Diabetes of the Young. Retrieved on June 19, 2010 from Diabetes Monitor: https://www.diabetesmonitor.com/mody.htm

Image Credits

Blood Sugar Monitor: foobean01 – Wikimedia Commons