Costa speculates that the decreased levels of reelin may be indirectly related to this phenomenon. First, a defect in the gene for reelin causes the misplacement of cortical neurons. This misplacement alone is not sufficient to precipitate mental illness, according to Costa. This first hit is then followed by a second hit later in puberty or in early adulthood when the final pruning of neuronal connections occurs. While this pruning is a normal part of brain maturation, Costa speculates that in schizophrenics it somehow unveils the defects laid down during fetal development.
Schizophrenia typically becomes evident when individuals are in their late teens or early twenties.
We may one day be able to alter the gene's mechanisms that regulate the production of reelin. Moreover, early identification of the genetic defect through laboratory analysis, which is currently under study at UIC by Dr. Smalheiser, might help us take remedial steps before psychotic symptoms arise. The Psychiatric Institute is part of UIC's College of Medicine , which is the nation's largest medical school. One out of six Illinois doctors is a graduate of the college, as are 70 percent of the minority physicians practicing in Chicago. The college produces more medical school faculty than all but five schools in the country.