Objectives: We aimed to identify the origin of atypical diabetes in a family with four generations of diabetes from South Asia. The family members showed different clinical phenotypes. Members of generation one to three were presumed to have type 2 diabetes and generation four to have type 1 diabetes.

Case presentation: We performed a genetic analysis of the family using targeted high throughput sequencing.

Conclusions: We identified a novel nonsense variant in the neurogenic differentiation 1 (NEUROD1 ) gene, co-segregating with diabetes. The variant was located in the DNA-binding domain, altering a protein residue that was very well conserved among different species.