Treatment of FXS patient lymphoblasts with general histone deacetylase (HDAC) inhibitors partially reverses transcriptional silencing in lymphoblastoid cell lines[53] and treatment of FXS patients with valproic acid, an antiepileptic and mood stabilizing drug with HDAC inhibitor activity, has produced promising preliminary results [54]. This evidence concerns the gene HDAC9 and fragile X syndrome.