A ONECUT1 regulatory, non-coding region in pancreatic development and diabetes.

In a patient with permanent neonatal syndromic diabetes clinically similar to cases with ONECUT1 biallelic mutations, we identified a disease-causing deletion located upstream of ONECUT1. Through genetic, genomic, and functional studies, we identified a crucial regulatory region acting as an enhancer of ONECUT1 specifically during pancreatic development. This enhancer region contains a low-frequency variant showing a strong association with type 2 diabetes and other glycemic traits, thus extending the contribution of this region to common forms of diabetes. Clinical relevance is provided by experimentally tailored therapy options for patients carrying ONECUT1 coding or regulatory mutations.