Similar findings were observed by Guo et al. [43], who treated young Mecp2-null mice that exhibited symptoms of Rett syndrome due to MeCP2 deficiency with 350 mg/kg VPA for 2 weeks and found significant improvement in their clinical symptoms and enhanced expression of MeCP2 gene in the brain compared to non-treated mice. Here, MECP2 is linked to atypical Rett syndrome.