Since FMRP negatively regulates MMP‐9 mRNA translation and the variant resulting in lower MMP‐9 activity at the spines (CC/CT) is the “risk” variant, one could speculate that the downregulation of FMRP in schizophrenia is even a compensatory mechanism to overcome decreased MMP‐9 levels. This evidence concerns the gene MMP9 and schizophrenia.