A novel nonsense mutation c.747C>G in the NEUROD1 gene detected within a Chinese family affected by maturity-onset diabetes of the young type 6.

Highlights Maturity-onset diabetes of the young type 6 (MODY6) is a rare form of monogenic diabetes mellitus due to NEUROD1 gene mutation on chromosome 2q32. A 21-year-old woman exhibiting weight loss, polyuria, and hyperglycemia was initially misdiagnosed with type 1 diabetes mellitus. Considering the early-onset age, a three-generation family history of diabetes, and negative autoimmune antibodies, a MODY diagnosis was suspected. Genetic analysis revealed that she inherited a novel heterozygous nonsense NEUROD1 mutation c.747C>G (p.Tyr249*) from her father. Correct MODY6 diagnosis facilitates appropriate interventions.