New research by Vanderbelt University Medical Center is expanding on the phenomenon of "hyperserotonemia" where high levels of serotonin are present in children with autism. They are able to now show a physcial basis for hyperserotonemia where a well known blood protein, integrin beta3, physically associates with and regulates the serotonin transporter (SERT). This protein controls serotonin availabilty, which when high levels of serotonin ocurr, mood swings can be a result.