We propose that Fmrp repression of E-cadherin (high Fmrp level) and other mRNA targets encoding for proteins that prevent tumour shedding together with an increase in proteins promoting invasion would support the enhanced ability of FMRP positive cells to detach from the primary tumour and invade allowing tumour spreading and subsequent metastases formation (Fig 5G). Here, CDH1 is linked to neoplasm.