They noted that confirmation through other studies is needed before such a link could be fully established. They also cautioned that in the history of schizophrenia research, many apparent associations had eventually proved spurious or impossible to replicate. One possibility, the researchers argue in their report, is that some cases of schizophrenia are a result of genetic abnormalities in sperm cells that become more likely to occur as a man ages. Stem cells in the testicles divide constantly through a man's life in a process that leads to the production of sperm. By age 40, research suggests, about 660 such divisions have taken place.
Mutations can also occur from exposure to radiation or chemicals over a man's life.
Other illnesses, defects In contrast, the divisions of cells that produce a woman's eggs occur only before birth. No studies, however, have found any relationship between mutations in older fathers and a psychiatric illness. Schizophrenia runs in families, and is known to have a strong genetic component. 2001 AzStarNet, Arizona Daily Star and its wire services and suppliers, and may not be republished without permission. All rights reserved.