FMR1 and fragile X syndrome: The results are suggestive that downregulation of FMRP‐deficiency in FMR1‐KO H1 and FXS μNETs resulted in the loss of β‐catenin specifically in the prospective NE, which destabilized the tissue architecture as evident by sporadic regional premature E‐to‐NCAD switching, accompanied by the acquisition of a migratory cellular phenotype.