The gene encodes a transcription activator for several genes involved in development and function of the endocrine pancreas. Mutations cause autosomal dominant diabetes MODY4. Pancreatic agenesis 1 with exocrine and endocrine pancreatic secretion and permanent neonatal diabetes mellitus is an autosomal recessive disorder.
| Clinic | Method | Carrier testing |
| Turnaround | 5 days | |
| Specimen type | genomic DNA |
| Clinic | Method | Massive parallel sequencing |
| Turnaround | 25 days | |
| Specimen type | genomic DNA |
| Clinic | Method | Genomic sequencing of the entire coding region |
| Turnaround | 25 days | |
| Specimen type | genomic DNA |
| Clinic | Method | Multiplex Ligation-Dependent Probe Amplification |
| Turnaround | 25 days | |
| Specimen type | genomic DNA |