Expression patterns of ciliopathy genes ARL3 and CEP120 reveal roles in multisystem development

BackgroundJoubert syndrome and related disorders (JSRD) and Jeune syndrome are multisystem ciliopathy disorders with overlapping phenotypes. There are a growing number of genetic causes for these rare syndromes, including the recently described genesARL3andCEP120.MethodsWe sought to explore the developmental expression patterns ofARL3andCEP120in humans to gain additional understanding of these genetic conditions. We used an RNA in situ detection technique called RNAscope to characteriseARL3andCEP120expression patterns in human embryos and foetuses in collaboration with the MRC-Wellcome Trust Human Developmental Biology Resource.ResultsBothARL3andCEP120are expressed in early human brain development, including the cerebellum and in the developing retina and kidney, consistent with the clinical phenotypes seen with pathogenic variants in these genes.ConclusionsThis study provides insights into the potential pathogenesis of JSRD by uncovering the spatial expression of two JSRD-causative genes during normal human development.