The gene encodes a transcription factor, which regulates among others the transcription of HNF1-alpha. When mutated, it causes autosomal dominant MODY1 diabetes and hyperinsulinemic hypoglycemia.
Along with MODY1 the mutation R76W can cause atypical dominant Fanconi syndrome.[Error: Macro 'ref' doesn't exist]
| 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 | 20 days | |
| Specimen type | genomic DNA |