Recently, our de novo brain-based proteomic screen study identified several proteins, including Ras (RAS), Hexokinase 1 (HK1), and Aconitase 2 (ACO2), with decreased expression levels in the Fmr1 KO hippocampus and in the peripheral blood of individuals with FXS [25]. This evidence concerns the gene ACO2 and fragile X syndrome.