YIPF5 mutations cause neonatal diabetes and microcephaly: progress for precision medicine and mechanistic understanding.

Identifying genes that result in monogenic diabetes can provide insights that can build a scientific foundation for precision medicine. At present, nearly 20% of neonatal diabetes cases have unknown causes. In this issue of the JCI, De Franco and Lytrivi et al. sequenced the genome of two probands with a rare neonatal diabetes subtype that also associated with microcephaly and epilepsy. The authors revealed mutations in the YIPF5 gene. YIPF5 resides in the Golgi apparatus and is thought to play a critical role in vesicular trafficking. Notably, disrupting YIPF5 in β cell-based models induced ER stress signaling and resulted in the accumulation of intracellular proinsulin. We believe that utilizing registries and biobanks to reveal other monogenic atypical forms of diabetes is an important approach to gaining insight and suggest that an insulin sensitizer may alleviate ER stress associated with YIPF5 disruption by decreasing the demand for insulin secretion.