In April 2000, with the British MMR scare in full flower and thousands of alarmed parents refusing to vaccinate their kids, scientists Andrew Wakefield and John O'Leary appeared in the circus-like hearing room of Rep. Dan Burton (R-Ind) to present their evidence that the measles-mumps-rubella "jab" was causing a gut infection that turned kids autistic.
With the approval of the partisan audience attending the Government Reform Committee hearing, O'Leary stated that his laboratory had found measles in 24 of the 25 samples from the GI tracts of autistic children under the care of Wakefield, whose 1998 article in the Lancet had kicked off the theory that MMR vaccination caused autism.
Since then, the Wakefield/O'Leary theory has moved through several scientific laboratories and into British and American courtrooms. Millions of dollars have been spent investigating it. In testimony this week, government witnesses attempted to deliver the death blow.
In 2000, as O'Leary and Wakefield testified before Burton, a conservative Republican who believes that his grandson got autism from vaccines, several hundred British parents were building a lawsuit over the MMR vaccine. Under the British system, their efforts were funded by the government. But as the investigation proceeded, serious accusations arose about the reliability of O'Leary's lab. Eventually, two papers were published that refuted the finding, and an exhaustive investigation of the lab led the British government to withdraw funding.
On Wednesday, the issue moved squarely into U.S. "vaccine court," where testimony was heard from Stephen A. Bustin, the British scientist who conducted the investigation and in the process probably did more than anyone else to puncture the MMR balloon.
Bustin's testimony, in the case of a 12-year-old autistic girl, Michelle Cedillo, was an intriguing voyage into the labyrinth of polymerase chain reaction--PCR--the technology used to amplify and identify miniscule genetic particles. The plaintiffs, not surprisingly, disputed that Bustin had authoritatively busted O'Leary's findings. It will be up to Special Master George Hastings to decide which side's evidence he believes the most.
But if nothing else, the testimony by Bustin and other witnesses this week provided an opportunity to reflect on the extent to which the vaccines-cause-autism case is built upon the use--and abuse if you agree with the government's witnesses-- of new tools of biological discovery that have emerged over the past few decades. These tools--PCR, advanced flow cytometry, endoscopy and the Internet, to name four--are wonderful ways to observe small things. They are fabulous tools for science and medicine, and the public, but they are tricky.
The Cedillo legal team's theory, presented last Friday by pediatric neurologist Marcel Kinsbourne, is that measles vaccine virus infects the gut and enters the brain, causing dysfunction of astrocytes and other brain cells, which in turn provokes high levels of the neurotransmitter glutatmate, causing a state of overstimulation which manifests itself in the symptoms of autism.
Kinsbourne, who made little mention of thimerosal in his testimony, said that measles detection in the autistic children was the key. Without it, Kinsbourne said, he would no longer stand by his hypothesis. Thus the government witnesses focused their attack on the O'Leary lab results.
Bustin is chairman of the department of molecular sciences at the University of London and author of "The A to Z of Quantitative PCR," which has been described as the Bible of PCR. In excruciating detail, he described how he had spent 150 hours investigating O'Leary's Unigenetics laboratory in Dublin, coming away with the conclusion that it was contaminated, and that its findings of measles in autistic children were not to be relied upon.
It was O'Leary's claim that he had used PCR to find measles fragments in the autistic children that gave the vaccines-cause-autism theory its first piece of tangible evidence. This became increasingly important in recent years after 14 consecutive epidemiological studies showed that kids who got the MMR shot were no more likely than those who didn't to become autistic.
But PCR, like other high-tech tools, is extremely sensitive and easily screwed up. The court must realize, testified Brian J. Ward, a Canadian virologist who led a study that could not replicate O'Leary's findings, that PCR is not a "magically sensitive technology where you walk in, put the sample in a machine, push a button and get truth on the other end. Those of us who have struggled with PCR would wish that were true, but like any other technology it's subject to a number of vagaries."
In PCR, a primer for a particular strand of DNA is introduced into a small bath containing the sample; if it finds a match the bound material can be amplified, with enzymes, until it can be perceived with fluorescence. In O'Leary's lab, primers similar to measles genes were introduced in the solution. But Bustin turned up what he felt were a number of problems. In the end, he decided that what O'Leary was calling measles RNA was actually human DNA with similar genetic sequences.
"I'm not convinced they found any measles RNA," he concluded.
In other testimony, Dr. Christine T. McCusker, a Canadian pediatric immunologist, stated Thursday that Cedillo's physicians and expert witnesses had misinterpreted levels of particular antibodies and cell types in her blood--also using new tools for disease detection and prevention--when they said that these levels showed she had an immune system skewed toward autoimmunity.
Dr. Stephen B. Hanauer, a gastroenterologist from the University of Chicago, argued that the abnormalities Cedillo's witnesses had described in her bowels were simply artifacts of looking at them up close with a "pill-cam," a device that is swallowed and wirelessly transmits images as it travels down the gut canal. He disputed that she had Crohn's disease, which some have linked to the measles vaccine.
The testimony of Bustin and Ward had particularly devastating implications. Hundreds of autistic children have undergone colonoscopies and biopsies, in part to treat their bowel problems, but also to provide gut samples for Unigenetics to search for evidence of measles vaccine virus. The Internet, another high-tech tool, has spread the word around the autism community about the possible benefits of this approach to treatment--and to finding a culprit for the disorder.
O'Leary's defenders, including plaintiff's witness Vera Byers last week, stated that since Ward and other scientists have only examined immune cells in autistic childrens' blood, rather than gut samples, their negative findings were irrelevant. But Ward and Bustin argued that if the alleged gut infection by measles vaccine virus had spread to the brain, it would have to get there through those same white blood cells.
In a further attack on the case, pediatric neurologist Max Wiznitzer, from Case Western Reserve Medical School in Cleveland, disputed that Michelle Cedillo had been developing normally before suffering a regression into autism--a key part of the plaintiff's argument. After reviewing her records and videotapes of her first 16 months of life, Wiznitzer said, it was clear she was autistic well before the MMR shot.
It is a bitter pill for parents who believe their child was taken from them by vaccines to argue, in effect, that she was never really with them to begin with--at least not in the way they imagine. But in his view of the videotapes, Wiznitzer said, he found that Michelle "shows no interest in sharing the excitement of the moment."
It's possible that there is no one to blame for autism but God--or chance.