Scientists at Columbia University Mailman School of Public Health's Center for Infection and Immunity, the Centers for Disease Control and Prevention, Massachusetts General Hospital and Trinity College Dublin evaluated bowel tissues from 25 children with autism and gastrointestinal disturbances and 13 children with gastrointestinal disturbances alone (controls) by real-time reverse transcription for the presence of measles virus RNA.

Samples were analyzed in three laboratories.

"Our results are inconsistent with a causal role for measles, mumps, rubella vaccine as a trigger or exacerbator of either gastrointestinal difficulties or autism," co-corresponding study author Mady Hornig of the Mailman School said in a statement. "The work reported here eliminates the remaining support for the hypothesis that autism with gastrointestinal complaints is related to measles, mumps, rubella vaccine exposure. We found no relationship between the timing of measles, mumps, rubella vaccine and the onset of either gastrointestinal complaints or autism."

The findings are published in the journal Public Library of Science.