These include FGFR1 tyrosine kinase domain duplication in low grade glioma, FGFR1-TACC1 fusions in extraventricular neurocytoma (EVN), and FGFR2-CTNNA3 fusions in polymorphous low grade neuroepithelial tumor of the young (PLNTY). The gene discussed is CTNNA3; the disease is neuroepithelial neoplasm.