Deletion of this gene in mice leads to the decrease in synaptic coverage by astrocytic leaflets, which translates into reduced densities of glutamatergic synapses.512 Deficits of astrocytic support of synaptogenesis can also be linked to a decrease in secretion of astrocyte-specific synaptogenic molecules such as hevin, SPARC proteins and thrombospondin-1.513,514 Astrocytes from FMR1 knockout mouse model of fragile X syndrome were characterised by an enhanced secretion pf interleukin-6 and tenascin C, as well as by increased purinergic signalling.515. The gene discussed is FMR1; the disease is fragile X syndrome.