A top science adviser is severing ties with Autism Speaks over disagreements with the organization on the issue of vaccine research months after an executive from the organization defected for the same reason.

Dr. Eric London resigned this week from his position on the Autism Speaks Scientific Affairs Committee citing the organization’s continued research into a link between vaccines and autism. In January, Alison Singer left her position as Autism Speaks’ executive vice president of communications and awareness citing similar concerns.

In his resignation letter, London says that Autism Speaks’ stance that “parents need even further assurances and there might be rare cases of ‘biologically plausible’ vaccine involvement” is “misleading and disingenuous.”

Further, London says, “through its Web site and other communications, Autism Speaks has been influential and contributory in encouraging parents’ doubts. By preferentially investing and advocating for the use of limited financial resources on the ‘biological plausibility’ argument, the organization is adversely impacting the advancement of autism research.”

For its part, an Autism Speaks spokesman says vaccine-related research is just one component of the group’s work.

“In 2008, Autism Speaks had a scientific research budget of $33 million. Approximately 2 percent of that funding — less than $800,000 — was directed toward vaccine-related research,” Adam Pockriss, an Autism Speaks spokesman, tells Disability Scoop.

Further, a statement from the organization says, “Autism Speaks is currently pursuing a broad program of research, including studies on both genetic and environmental risk factors and the development of new treatments. We believe that our broad agenda will ultimately provide answers to the cause and treatment of autism spectrum disorders. We wish Dr. London well in his new endeavor.”

London’s resignation was publicly announced by the Autism Science Foundation, a rival group founded by Singer earlier this year.

London co-founded the National Alliance for Autism Research, which merged with Autism Speaks in 2006. He now serves on the Autism Science Foundation’s scientific advisory board.

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