What is mature-onset diabetes of the young type 5 (MODY 5)?

MODY 5 is a form of diabetes caused by a mutation of a single gene. The mutation causes pancreatic beta cells to function abnormally, leading to insufficient production of insulin. In some cases, insulin resistance develops. In addition, the pancreas may not produce enough digestive enzymes.

Symptoms of MODY 5

Outward signs of MODY 5 are similar to those for the more common forms of diabetes:

• Frequent urination
• Excessive thirst
• Dehydration

In addition, children with MODY 5 may have symptoms related to decreased production of digestive enzymes, leaving partially digested food in the GI tract:

• Crampy abdominal pain
• Gas and bloating
• Foul-smelling, greasy diarrhea
• Poor weight gain
• Weight loss

Diagnosis of MODY 5

The diagnosis of MODY 5 is made after observing the child’s symptoms and taking a history, including a family history. If symptoms suggest diabetes, blood tests are done to measure:

• Glucose levels
• How much insulin the body is making
• The presence or absence of autoantibodies

High glucose levels and low insulin indicate diabetes, and the absence of autoantibodies rules out type 1 diabetes. If the symptoms, history and tests suggest MODY 5, a genetic test is performed, initially for the child and possibly for immediate family members, to confirm the diagnosis and identify the specific gene mutation. A mutation in the TCF2 or HNF1B gene confirms the diagnosis of MODY 5.

Treatment for MODY 5

Pancreatic insufficiency caused by MODY 5 is treated with medications that contain the missing digestive enzymes, available by prescription from a healthcare provider.

At Children's Hospital of Philadelphia (CHOP), children with MODY 5 are evaluated and treated by doctors in the Pancreatic Disorders Program in the Division of Gastroenterology, Hepatology and Nutrition and the Division of Endocrinology.