Thirteen fetuses/newborns with complete loss-of-function COASY variants exhibited pontocerebellar hypoplasia type 12 (PCH12), a fatal inherited neurodevelopmental disorder characterized by microcephaly and perinatal death, without brain iron accumulation (van Dijk et al., 2018; Mishra et al., 2022). Here, COASY is linked to Non-syndromic pontocerebellar hypoplasia.