WE CAN ALL think of famous figures throughout history who were haunted by the voices and hallucinations of schizophrenia, but how far back in mankind's past can we trace the origins of the disease? British scientist Dr. David Horrobin, author of The Madness of Adam and Eve, argues that schizophrenia signaled the beginnings of modern man: A genetic mutation changed the biochemistry of fat in our brains. This mutation instigated the ascendancy of Homo sapiens, but brought with it the burden of mental illness as well. If Horrobin is right, his hypothesis will change evolutionary biology and the way we treat schizophrenia.

Roughly one percent of the population is schizophrenic; the disease is the most uniformly distributed in the world, found in every race and on every continent. Horrobin concludes that the genetic mutations must have occurred before the separation of the races some 50,000 to 150,000 years ago. One family with the mutation, and the intelligence, curiosity, creativity, and pathology that came with it, set out from Africa to "conquer the globe," eventually killing off Homo erectus and Neanderthals. The change in brain chemistry led to religion, art, and symbolic activity, but it also led to psychopathic tendencies. And as groups settled and created agrarian societies, their diets included less essential fatty acids, heightening the negative effects of schizophrenia.

The essential fatty acids (EFAs) found in the phospholipids that make up axons and dendrites are necessary for the brain's growth and development, and its control of chemical signals. Horrobin believes that the release of EFAs in schizophrenics is impaired due to a combination of genes. (There may be a single "psychosis gene" and several other genes that determine which illness will be predominant -- schizophrenia, bipolar disorder, or sociopathy.) Horrobin initially suggested the connection between schizophrenia and phospholipids over twenty years ago, but it is only recently that the medical community has started to take it seriously.

Though studies administering EFA supplements to schizophrenics have shown promising results, Horribin's hypotheses are still met with skepticism. The drugs currently used to treat schizophrenia have a 15-25% success rate in the improvement of symptoms. Horrobin's own study produced a 22% overall success rate, but with one extremely important difference: His treatment didn't have the side effects of most drugs -- weight gain, hypersalivation, and tardive dyskinesia (uncontrollable twitching and writhing movements). Another study using EFA produced not only a 43% success rate, but actually showed that the damage to the brain was reversing. The treatment? A supplement extracted from fish. And as Horribin points out in his book, "embarrassingly for Western medicine," a study conducted by the World Health Organization in the 1970s showed that schizophrenics in industrialized nations tended to have more chronic, severe symptoms than in other countries. He suggests that "experts in biological aspects of psychiatry like the idea of a biochemical explanation but sometimes seem to hate the idea that the biochemistry may be related to nutrition rather than to some ultra-modern, and what they see as sophisticated, molecular biology." Not to mention that there's a lot more money to be made in pharmaceuticals than in fish oil -- a cynical notion, but a reality nonetheless. Even as more and more doctors turn to herbal and nutritional treatments, there are only about twenty groups of researchers pursuing the EFA-schizophrenia link.

Fat may be the answer to schizophrenia, but so far, no one has solved the mystery of the disease's origins. New studies suggesting different causes come out all the time: Last month, a Johns Hopkins study reported findings of viral "foot-prints" in the cerebrospinal fluid of newly diagnosed schizophrenics. Another study found differences in the genes that regulate myelin, and yet another study of over 87,000 Israelis proposed a connection between the disease and the age of one's father at conception. Identifying specific genes that cause schizophrenia holds great promise for a cure, but it will be years, perhaps decades, before researchers can test Horrobin's striking evolutionary hypothesis.