MINPP1 and nervous system disorder: Although we still do not have clear functional proof of causality between MINPP1 variants identified in four families and the observed clinical phenotype, based on the noncoincidental overlap of features and genotypes of the affected children as well as the relevance of the inositol phosphatase metabolism to neurological disorders (including PCH), we conclude that sequence variants in MINPP1 are associated with a new form of syndromic pontocerebellar hypoplasia.