Hydrolethalus Syndrome 1, also known as hydrolethalus syndrome, is related to hydrolethalus syndrome 2 and acrocallosal syndrome. An important gene associated with Hydrolethalus Syndrome 1 is HYLS1 (HYLS1 Centriolar And Ciliogenesis Associated), and among its related pathways/superpathways are Loss of Nlp from mitotic centrosomes and Organelle biogenesis and maintenance. Affiliated tissues include heart and adrenal gland, and related phenotypes are agenesis of corpus callosum and hydrocephalus