Mady Hornig

Mady Hornig, MD (born 1957) is a psychiatrist and an associate professor of epidemiology at Columbia University's Mailman School of Public Health, where she is Director of Translational Research in the Center for Infection and Immunity (CII). A physician-scientist, her research involves clinical, epidemiological, and animal model research on autism and related neurodevelopmental conditions. She directs the clinical core of an international investigation of the role of Borna disease virus in human mental illness and participates as a key investigator for the Autism Birth Cohort (ABC) project, a large prospective epidemiological study, based in Norway, that is identifying how genes and timing interact with environmental agents preceding the onset of autism spectrum diagnoses. In 2006, she was appointed as Guest Professor at the School of Basic Medical Science of Beijing University in Beijing, China.

Hornig is investigating the role of viral and immune system factors affecting mental health. Along with CII director W. Ian Lipkin and colleague Thomas Briese, she is currently investigating measles virus DNA sequences in bowel biopsies of children with autism spectrum disorders. Formulating a ‘three strikes’ model of causation that integrates genetics, the environment and developmental neurobiology, Hornig posits that some cases of autism may represent the unfortunate coincidence of genetic vulnerability (first dimension) and exposure to environmental factors (second dimension) at a critical period of brain development (third dimension). She is examining how brain damage from infections, immune system dysfunction, neurotoxins, and other chemical or psychosocial stress factors, or host responses to these environmental agents, can lead to neurodevelopmental and other central nervous system disorders, thereby contributing to autism, schizophrenia, attention deficit hyperactivity disorder, obsessive compulsive disorders, and mood disorders.

Education
Dr. Hornig received a bachelor's degree in 1978 from Cornell University, where she was a College Scholar; an MA in psychology in 1983 from the New School for Social Research, and an MD in 1988 from the Medical College of Pennsylvania, in Philadelphia. Between 1988 and 1992, Hornig served her residency in psychiatry at the University of Vermont. Under a National Research Service Award from the National Institutes of Mental Health, she completed a postdoctoral fellowship in neuropsychopharmacology on the Depression Research Unit of the University of Pennsylvania from 1992 to 1994.

Career
Hornig is widely recognized for her work on the role of microbial and immune factors in mental illness and neurodevelopmental disorders. In 1997, Hornig discovered a link between blood flow to brain regions regulating emotion and memory, stress hormones, and treatment failure in people with major depression, setting the stage for development of biomarkers that could match patients to the interventions most likely to help them. She is also known for her animal model research suggesting how specific gene variants (polymorphisms) present in a subset of the population may create exaggerated vulnerability to subtoxic exposures of heavy metals and other common environmental pollutants, corroborating similar findings by Jill James, Richard Deth, David Baskin, and Boyd Haley, among others.

Within the Northeast Biodefense Center, an NIAID regional Center of Excellence in biodefense and emerging infectious diseases, Hornig is a member of the Core Oversight Committee and the Governing Council, leading a project on immune and neuroendocrine factors in West Nile virus encephalitis.

Hornig's multidisciplinary research methods integrate data from animal models and epidemiological studies, incorporating behavioral, neurochemical, neuroendocrine, neurostructural, molecular, immunologic and microbiologic perspectives. Hornig uses clues from animal models and epidemiological studies to understand the neurodevelopmental responses to environmental factors during brain maturation that may trigger or amplify psychiatric conditions.

In 2004, she was elected to the President’s Council of Cornell Women, serving as Dean’s Liaison for Cornell Weill Medical College; she is a member of the New York Academy of Sciences Frontiers of Science Steering Committee; serves in the Medical Reserve Corps for the NYC Department of Health and Mental Hygiene; and sits on the board of directors for The DisAbility Project in Saint Louis, Missouri.

In 2008, she published a study concluding that there was no association between presence of measles vaccine virus in the gut of children and whether these children had autism, nor was there an association between MMR exposure and autism.

Animal models
In the 1990s, Hornig helped to develop an infection-based model of neurodevelopmental disorders, such as autism, based on neonatal rat infection with Borna disease virus.

In 2004, Hornig published a controversial paper concluding that, in a highly inbred strain of mice which is unusually susceptible to autoimmune disease, administration of thimerosal resulted in the development of autism-like symptoms; specifically, "growth delay; reduced locomotion; exaggerated response to novelty; and densely packed, hyperchromic hippocampal neurons with altered glutamate receptors and transporters." In addition, in an interview with the Los Angeles Times, Hornig contended that thimerosal may be linked to the recent increases in the incidence of autism. However, Paul Offit has accused Hornig of overstating her findings, arguing that her study was "a far cry from proving that thimerosal caused autism in children," and Steven Goodman, a member of the IOM panel that rejected a thimerosal-autism link in 2004, shortly before Hornig's study was published, has claimed that this study "in no way substitutes for actual human evidence."

In 2006, Dan Olmsted reported that Hornig was working on a treatment program in which she would administer gold salts to these genetically susceptible mice in an attempt to improve their behavior.

Personal life
Dr. Hornig is a native of Brooklyn. She married Jim Hornig-Rohan in 1979. They met at the Cancer Institute of Harvard Medical School, when both were doing research in immunology. They have a child, Russell, who was born in July 1985.

Select publications

 * Steven Locke, Mady Honig-Rohan, Mind and Immunity:  Behavioral Immunology, 1983, ISBN 0-275-91400-3
 * Jay D. Amsterdam, Mady Hornig, Andrew A. Nierenberg (editors), Treatment-Resistant Mood Disorders, 2001, ISBN 0-521-59341-7
 * Hornig M., Chian D., Lipkin W.I., 'Neurotoxic effects of postnatal thimerosal are mouse strain dependent', Molecular Psychiatry (September, 2004)
 * Mady Hornig, Thomas Briese, Timothy Buie, Margaret L. Bauman, Gregory Lauwers, Ulrike Siemetzki, Kimberly Hummel, Paul A. Rota, William J. Bellini, John J. O'Leary, Orla Sheils, Errol Alden, Larry Pickering, W. Ian Lipkin - 'Lack of Association between Measles Virus Vaccine and Autism with Enteropathy: A Case-Control Study', PLoS ONE (September, 2008)
 * Mady Hornig, Thomas Briese, Timothy Buie, Margaret L. Bauman, Gregory Lauwers, Ulrike Siemetzki, Kimberly Hummel, Paul A. Rota, William J. Bellini, John J. O'Leary, Orla Sheils, Errol Alden, Larry Pickering, W. Ian Lipkin - 'Lack of Association between Measles Virus Vaccine and Autism with Enteropathy: A Case-Control Study', PLoS ONE (September, 2008)