YIPF5 and microcephaly: For example, recessive YIPF5 variants were found by initially searching for the cause of 2 patients with the same extra-pancreatic phenotype before replication studies helped to identify a total of 5 families with a syndrome of neonatal diabetes, epilepsy, and severe microcephaly.15 Both MANF and YIPF5 are involved in endoplasmic reticulum stress regulation, and these disease associations have highlighted the importance of this pathway for proper human β-cell function.