March 23, 2008
At-Home Test For Bipolar Disorder Causes Concern
Last December, Dr. John Kelsoe, a prominent psychiatric geneticist at the University of California who had spent his entire career identifying the biological roots of bipolar disorder, announced he had discovered several gene mutations closely associated with the disease.
Then, Kelsoe, 52, did something unheard of in the world of academic research by selling genetic tests for the condition directly to the public via the Internet for $399.
Although Psynomics has sold only a few tests so far, the company is projecting sales of 1,800 tests this year and 30,000 in the next five years.
But many public health officials, doctors and medical ethicists worry about the proliferation of these tests, which are without any significant government oversight, even though many of them are being sold as tools for making important medical decisions.
Experts are concerned that many of these tests prey on people's deepest anxieties, and are based on shaky data.
"People are always rushing to the market on the basis of one or two studies," Dr. Muin Khoury, director of the National Office of Public Health Genomics at the Centers for Disease Control and Prevention (CDC), told the Associated Press.
"We have very little evidence that telling people their genetic information is going to make any difference."
Some of the available tests claim the ability to predict and diagnose conditions as wide ranging as cancer, Alzheimer's disease, athletic ability and even a person's ideal diet.
However, Psynomics' offering is one of the first psychiatric gene tests on the market.
Kelsoe admits that bipolar disorder is likely the result of a combination of both genetic and life experience factors, and that the presence of certain gene variations alone does not indicate someone will, in fact, develop the disease. He also acknowledges that his studies about the genetic basis of manic depression are incomplete.
But he said his test is a critical starting point in the departure from the notoriously tricky practice of diagnosing bipolar disorder based solely on a person's behavior.
"The goal of this is to try and help doctors make an accurate diagnosis more quickly so the patient can be treated appropriately," Kelsoe told the AP.
"Anything is going to help, even if it just helps a little bit."
People with bipolar disorder experience intense mood swings, cycling through delusional highs and depressive lows that untreated could lead to suicide. The disease is often misdiagnosed as depression, delaying proper treatment and resulting in improper prescribing of medications such as antidepressants that could even aggregate symptoms in some patients.
To take the Psynomics test, patients spit into a plastic cup they receive by mail from the company, and then seal and return the cup to Psynomics, who then analyze the DNA in the saliva. To avoid self-diagnosis by the customer, Psynomics will only send test results to the customer's doctor, along with an accompanying report instructing the doctor that a positive test means patients are two to three times more likely to have bipolar disorder.
But the studies from which those figures derive also show such gene mutations are rare, even among those with bipolar disorder.
For now, the test is valid only in whites of Northern European ancestry who demonstrate some behavioral symptoms and have at least one bipolar family member.
Hank Greely, a professor of law and genetics with the Stanford Center for Biomedical Ethics, said patients taking Psynomics' bipolar test might feel branded by a positive result, even if they are not ultimately found to have the disorder. Or, on the other hand, they may get a false hope from a negative result, despite Psynomics' disclaimers about the test.
Doctors have little training beyond what companies such as Psynomics tell them when it comes to interpreting and applying the test results.
"They may make a foolish decision that backfires to put you on meds," Greely told the Associated Press.
"Or they may make a decision that backfires not to put you on meds."
The Psynomics test is intended only to be used as a purely diagnostic tool for patients already showing symptoms, unlike tests on the market for other conditions. And the company does not claim its test can predict a person's risk of developing bipolar disorder later in life.
According to Dr. Greg Feero, head of genomic health care at the National Human Genome Research Institute, it's an important distinction that differentiates Psynomics as more responsible than others that promise a glimpse into the future.
"Now you're talking about an individual who has symptoms or signs that already put them in a very different risk category than someone who has no symptoms or signs," Feero told AP.
Kelsoe has studied hundreds of families, and discovered one of the gene variations in the Psynomics test showed up in 1 percent of those unaffected by bipolar disorder versus 3 percent who are affected. Another variation appeared in 7 percent of those without the disorder, compared to 15 percent who have the disease.
Kelsoe and his team believe that no single genetic variation is ultimately responsible for bipolar disorder, and many other genes outside of those identified by Kelsoe interact with a patient's environment to contribute to the development of the disease. Researchers in Kelsoe's lab are working to identify more genes.
"Why are we starting before it's finished? You've got to start somewhere," Kelsoe said. "Even if we knew everything about the genes, which we certainly don't, it's never going to be 100 percent predictive."
At least two other startups led by genetic researchers are set to release their own psychiatric genetic tests in the coming months -- one to predict a person's risk of developing schizophrenia, and the other to forecast the likelihood that some medications for major depression could intensify a patients' suicidal thoughts.
To date, the American Psychiatric Association has not yet adopted an official policy on genetic testing. A Federal Trade Commission fact sheet cautions consumers to be skeptical of claims made by at-home genetic testing companies. A Food and Drug Administration panel is working to establish standards for the nascent industry, but does not evaluate the tests for accuracy.
For now, many remain concerned about the proliferation of these tests, and that there is too little understanding of them to interpret the results.
"We just don't know how people will use the information," Dr. Jinger Hoop, a professor of psychiatric genetics and medical ethics at the Medical College of Wisconsin in Milwaukee, told the Associated Press.
"We don't know whether it will be helpful to them in the long run."