Genetic testing is one of the hot new topics in society and medicine. There are multiple companies providing a variety of types of genetic testing and for a wide assortment of circumstances. The most common we here about is for determining our heritage and background.

These are meant to tell us roughly what our genes tell us about where our ancestors are from  Most of these genetic tests take a very small look at selective areas of our chromosomes and do not perform a comprehensive analysis. The tests usually look at select genes that control a limited number of proteins in the body, not even a full one percent of the genetic information on our chromosomes.

These genetic tests that are marketed to consumers have limited value beyond curiosity for the average person. The accuracy is probably as good as a well researched family tree at best. Last year, a couple of these tests were done on a set of identical triplets. These three women have exactly the same genes, but the profiles produced from the genetic tests were not close to being identical. The take home message is that these tests are not at the level that they should be trusted beyond just stoking curiosity in one’s heritage. Any information above that level is mostly speculative.

The common genetic testing companies include 23 and Me as well as Ancestry.com. Besides providing basic information about likely ancestral history, they now are reporting the risk one might have toward some diseases. These include risk of Alzheimer’s and some types of cancer. However, most of these tests have recently been shown to have a false positive rate of 40 percent or higher. This is a result of these tests looking at only a small portion of genes in the total amount of chromosomes, and this approach is not very accurate. Further, these companies that are doing this commercial work often are not following procedures that have adequate quality controls. Thus a significant amount of false information is now being rendered to the average consumer, prompting often further expensive medical testing for the truth.

For the paranoid, these genetic testing results are often in public databases. Your genetic code is now available to the world and without your permission others could access this personal information. In the future this may be the next reason for a denial for insurance since you may have a gene linked to a “possible” medical disease. The government is certainly using the information in cold case databases. The “Golden Gate” murderer in California was traced down through this method. The next venue will likely be paternity cases for adoptions and artificial insemination or similar circumstances.

Medical Value of Genetic Testing

In the medical world, genetic testing does have some value, but in specific areas. The most significant so far are two general areas, identifying diseases that are genetically linked, and to help with finding the right medication for a person. In pain medicine, the ability to process certain medications to be effective in the body sometimes requires certain enzymes. For instance, the ability for hydrocodone (Norco, Vicoden, or Lortab) to be effective requires an enzyme to convert it to an active drug. Without that particular enzyme, hydrocodone is ineffective. Interestingly, all my children happen to be missing the enzyme and when they have had surgery they have had to explain this to all their treating physicians. Another common problem is that certain enzymes are needed to make some antidepressant drugs helpful. If the medication is not working, the patient may not be able to effectively use that particular class of drugs. Most of the time it is more effective just to switch to a different medication than to try to do testing, however if a simple switch does not work, then enzyme or genetic testing may be indicated.

Certain medical diseases definitely are genetically linked. Random genetic testing in someone who does not have medical issues is likely to be costly and currently not especially useful. However, if the person has significant medical issues, clearly identifying a known genetic disease can be helpful in order to know what future issues may be likely. Many of my pain patients happen to have hypermobility of the joints that is linked to abnormal connective tissue. There is a wide range of severity, but it can lead to significant problems from spine curvature, to eye problems and cardiac or vascular aneurysms. It is also often a dominant trait and can pass on to 50 percent of a person’s offspring. Knowing the disease can help in the long-term care and prevention of dangerous complications.

For the curious about ancestry, genetic testing can be fun, but the information may or may not be overly accurate. Know that the information may become part of a public database and the future problems of others knowing this information about you may have a negative impact on your life. If you have certain medical conditions, genetic testing now may become helpful in managing your disease. If you are having problems with a medical condition, sometimes looking deep into a person’s genetic code may reveal helpful guidance, but this should be done with the help of an appropriate medical professional.