Many companies are now offering
self-administered genetic tests over the internet for various conditions, including
ADHD and
Bipolar Disorder. However, many of these tests might be misleading to the public because they offer predictions that are not scientifically proven and may provide information that is not meaningful.
Genetic testing looks at genes (DNA instructions inherited from relatives), chromosomes (contain DNA), or biochemical tests that test for enzyme levels. Genetic testing might help diagnose a disease or condition if someone already has symptoms, show whether someone is a carrier for certain genetic conditions, determine whether an unborn child will have a genetic condition, screen infants for missing proteins that can cause a disease, determine whether someone has a genetic predisposition to a disease before symptoms become apparent, and guide the selection of a particular medication or dose of medication for a particular person.
Testing is useful for rare types of cancers that run in families, for conditions such as
Sickle Cell Anemia and
Cystic Fibrosis, and for women who might be at risk for having a child with a chromosomal abnormality. However, I wouldn't send a sample of your saliva or cheek swab for psychiatric or behavioral conditions, along with a check for hundreds of dollars, just yet.
Where I find genetic testing sometimes useful is in determining the appropriate dose of
Strattera, a medication used to treat ADHD. Genes determine how rapidly a person's liver enzymes break down Strattera. People who metabolize Strattera slowly will have higher than expected blood levels of a particular dose of Strattera, along with increased side effects, and people who rapidly metabolize Strattera have lower than expected blood levels corresponding to a poor response. I might have to use very small doses of Strattera for someone who is a slow metabolizer to achieve the appropriate response without significant side effects, and large doses for someone who is a rapid metabolizer to achieve therapeutic blood levels.
ADHD is highly heritable. If one parent or a sibling has ADHD, additional children have about a 30 percent chance of inheriting it, which increases to 50 percent if both parents have ADHD. However, I don't find genetic testing useful for ADHD as it only determines the probability of developing ADHD, not whether someone has ADHD. What you would do for a child at risk of developing ADHD would be good for every child: providing structure, a nutritious and balanced diet low in sugar and high in
omega-3 fatty acids, plenty of exercise, and teaching them how to plan and organize their time for schoolwork and activities.
A child with a 30 percent chance of developing ADHD has a 70 percent chance of not developing it. Will genetic testing increase a parent's worry and change the way they interact with their child? Will everyone involved be so alert for signs and symptoms of ADHD that the child is at increased risk for getting a diagnosis when they don't have ADHD? ADHD most likely results from multiple genetic factors and the child's interactions with the environment. There is no genetic test that will diagnose ADHD, and the information provided by available tests tends to make little difference. Many internet sites are misleading, promising diets or nutritional additives that will avoid the use of medications. Someone should always check with their physician or genetic specialist prior to ordering self-administered genetic tests.
Related Topics: Technorati Tags: ADHD, bipolar, DNA, genetic test, home DNA testImage: istockphoto.com
