PSMA2 and fragile X syndrome: Alpha2-agonists, clonidine and guanfacine, showed about 62% efficacy in a clinic setting in treating hyperactive, hyperaroused, hypersensitive, impulsive, and aggressive behaviors due to overarousal in young boys with FXS, consistent with a survey study showing an 80% response rate for management of hyperarousal and hyperactivity.