The reason for this research study is to better understand the use of liraglutide, a commonly prescribed Type 2 diabetes medication, in patients with a diagnosis of maturity-onset diabetes of the young (MODY).

The investigators are interested in better understanding the way that this drug affects the metabolism and hormone levels of a person with MODY. Many people with MODY report having gastrointestinal (GI) issues such as an upset stomach. Investigators also are interested in finding out if this drug will help with GI issues.

If liraglutide does help with this symptom of MODY, the investigators want to know why this happens. If this drug is effective for participants, the investigators will use participants cells to make human induced pluripotent stem cell (iPSC). This means that the investigators will use participant cells to create what are called stem cells, which are cells in the body that are able to be told what their job is. Investigators will use these cells to see what happens in gastrointestinal (GI) tract.

The objective of this study is to perform a comprehensive metabolic and hormonal evaluation of individuals with Maturity-onset diabetes of the young (MODY) at baseline and then assess response to initiation of liraglutide. Select individuals will be consented for human induced pluripotent stem cell (iPSC) generation to identify the cellular basis of enteroendocrine cell (EEC) dysfunction.

The hypothesis is that heterozygous mutations in MODY-related genes contribute to a range of GI pathologies, including regional disruptions in epithelial identity and disturbances in the function of EECs. Thus, patients with MODY may experience improvement not only in HbA1c and BMI but also in GI symptoms with initiation of GLP-1 receptor agonists. Investigators plan to enroll approximately 50 patients with MODY and obtain baseline metabolic labs and imaging along with enteroendocrine labs before initiating liraglutide and assessing response with repeat labs and imaging. This project will provide further guidance for clinical care and treatment of patients with MODY.

Inclusion Criteria:

• Diagnosis of MODY via genetic testing
• HgbA1c >6.5%

Exclusion Criteria:

• History of anaphylaxis to GLP-1 receptor agonists
• Already taking GLP-1 receptor agonists
• on medications within the stimulant class
• have had bariatric surgery
• personal or family history of cancer, especially medullary thyroid cancer
• personal history of pancreatitis or pathogenic variants associated with increased risk of pancreatitis
• known active kidney disease
• severe hypoglycemia (glucose < 50 mg/dL) within 3 months of study enrollment
• HbA1c > 10.0%
• episode of diabetic ketoacidosis (DKA) in the past 3 months
• are currently pregnant
• BMI < 18.5 kg/m2 and pediatric patients with BMI < 5th percentile

individual participant data will not be made available to other researchers.