“My parents make me crazy” is one phrase you’re likely to hear often during this time of year. For those who have a history of mental illness in their family, it may be comforting to learn that new research suggests that genetics may not be the primary cause.
A new hypothesis is taking hold in the scientific community suggesting that schizophrenia, bipolar disorder and even multiple sclerosis may actually be caused by a virus. More surprisingly, it may be a virus that we all harbor within ourselves; an endogenous retrovirus called HERV-W. Retroviruses, when they enter the cell, splice their DNA into our own and can lay dormant for a very long time. An endogenous retrovirus is one that was spliced into the genome of a human progenitor millions of years ago and has long since become inactive “junk DNA."
Dr. Fuller Torrey from the Stanley Medical Institute in Maryland thinks schizophrenia may be caused when infection during pregnancy activates HERV-W retroviral DNA and production of viral proteins from the DNA. This can cause inflammation in the brain and other tissues as the body works to fight off this sudden invasion.
Since this revelation, studies have found HERV-W in the blood and brain fluids of 49% of schizophrenic patients compared to just 4% of a control group. Active HERV-W elements have also been found in MS patients. The damage to surrounding neurons due to inflammation may cause overstimulation, resulting in the hallucinations and paranoia experienced by schizophrenics. In MS patients, death of damaged neurons may be what causes eventual paralysis.
Schizophrenia affects more than 50 million people worldwide and is considered one of the most common mental illnesses. Despite its prevalence, very little is known about the causes of schizophrenia and, as a consequence, the treatments have made little progress. It was once thought that cold and distant mothers were to blame. When that theory was abandoned, it was replaced by the now common belief that a constellation of ‘bad’ genes passed down through families are responsible.
However, some quirky clues led researchers such as Dr. Fuller Torrey to rethink the root cause. For example, in data from 250 different studies, it was noticed that schizophrenics are likely to have birthdays in winter or early spring, a fact known as the “birth-month effect." The birth-month effect could be explained if schizophrenia and possibly other diseases are caused by infections that are more common during cold months.
Now the researchers are suggesting radical new treatments such as administering antibiotics and antiviral drugs along with other medications taken by schizophrenics in order to better suppress symptoms. They are also developing antibodies to target HERV-W directly. A detailed and fascinating account of Dr. Torrey’s quest to find the “Insanity Virus," including his own personal experience with the illness’s debilitating effect on his sister, can be read here.