From The Quarterly, Winter 2011
In 1991, NARSAD awarded a Young Investigator grant to W. Ian Lipkin, M.D., then at the University of California, Irvine, for a study of the Borna disease virus (BDV). His interest came from a surprising report of BDV infection in patients with bipolar disorder. Borna virus got its name from a German town where, a century earlier, it famously caused an outbreak of equine encephalitis, but in all the years thereafter no one had been able to isolate the virus. Bypassing established methods, Dr. Lipkin created his own method, captured the virus and went on to become one of the most inventive and renowned virus hunters in the world.
Today Dr. Lipkin is applying his vast expertise to the baffling questions surrounding the growing prevalence of autism: Is infection a trigger? Is the measles-mumps-rubella (MMR) vaccine a risk factor?
A virus is a very small entity, a handful of genes wrapped in protein, which survives by invading a living cell and basically taking over the cell’s functioning. Small size and the ability to hide in cells make viruses often hard to find.
Dr. Lipkin developed an ingenious molecular probe to tease out the BDV genes from the brains of infected animals. In the 20 years since, he and his colleagues have created ever more sophisticated techniques. While still at Irvine he identified West Nile Virus, not seen before on this continent, as the cause of the 1999 outbreak of encephalitis in New York. Now the John Snow Professor of Epidemiology and professor of neurology and pathology at Columbia University, Dr. Lipkin directs the Center for Infection and Immunity. Since his arrival in 2002, he and his team have examined tens of thousands of viruses and identified several hundred new ones.
Recently, his focus returned to the question of the role of viruses in brain disorders. While neither he nor anyone else has been able to replicate the original report of BDV infection associated with bipolar disorder, there is a growing body of research suggesting infection as a trigger for schizophrenia and autism in people with a genetic susceptibility. Autism is among the most heritable of neurodevelopmental disorders, but its pathogenesis remains unclear.
Dr. Lipkin’s team is now participating in a large multi-institutional project that includes the Norwegian Institute of Public Health and the U.S. National Institute of Neurological Disorders and Stroke, among others. A recent paper in Molecular Psychiatry titled “The Autism Birth Cohort: A Paradign for Gene-Environment-Timing Research” describes the study, which takes advantage of the more than 100,000 children regularly screened through the Norwegian Mother and Child Cohort. The Autism Birth Cohort (ABC) was designed to focus on prenatal or postnatal infection, diet, other environmental exposure to potential toxins and general obstetric risk factors that may contribute to the development of autism.
The idea that the MMR vaccine could induce autism in children was based on a British study conducted in 1998 that claimed measles in the vaccine released into the intestines might move to the brain. Numerous researchers have tried and failed to duplicate the initial study. Dr. Lipkin recently entered the fray and went on the hunt for measles’ viruses. He found no difference in virus levels in the intestines of autistic and normal children with gastrointestinal problems. The finding, which confirms other reports, is of major significance. As he explains, by failing to vaccinate their children, parents inadvertently run the greater risk of measles outbreaks.