Psynomics, a San Diego company, recently began Internet sales of a saliva test for bipolar disorder. For several hundred dollars anyone can buy the kit. After sending a sample to Psynomics, the company will return the results to the person's doctor.

This would be a great development to determine for sure whether someone has bipolar disorder...if it actually provided useful and reliable information.

The Psynomics test checks for the presence of particular mutations of a gene called GRK3, one of many genes that may be associated with bipolar disorder.

But there are some serious problems with this test. The identification of genes that may predispose someone to develop bipolar disorder is an exciting and important research area. However, the type of genetic testing being marketed to the public is highly premature and ill advised, and may lead to greater confusion about diagnoses.

Here are a few reasons why this test has become so controversial among some researchers and medical ethicists:

• A positive test result does not mean that people actually have or will develop bipolar disorder. It only means that their risk is slightly greater than that of the general population.
• A negative test result does not mean that they do not have bipolar disorder.
• The test is only meaningful for people of Northern European heritage (Caucasian).
• The test is only meaningful for people who already have some symptoms suggesting the presence of bipolar disorder.
• The test provides no useful information for people without psychiatric symptoms.
• The test provides no useful information for people who already have a clear diagnosis of bipolar disorder.

This bipolar disorder gene test is one of hundreds of similar tests developed to assess risk for many different health conditions. Currently, there is no government oversight of their reliability or value.

And, as with this bipolar disorder test, most such tests do not really identify whether someone has or will develop the condition. Rather, they indicate the presence or absence of a genetic variant that might be associated with the condition in some people.

This bipolar disorder test is not ready for prime time. But stay tuned. This type of testing may play an important role in the future.