Parents open to genetic tests for children

By Dr. Ananya Mandal, MDApr 19 2011

Genetic testing techniques have not been perfected yet but parents are willing to take the risk to know if their children are at risk for diseases in adulthood. Some parents would like the ability to predict the future, in terms of their child's risk for certain chronic health conditions. This comes in a new study published online in the journal Pediatrics. Experts, however, say the tests are of little value at this time.

The study done at Georgetown University, surveyed 219 parents who had been offered genetic testing for susceptibility to 8 common health conditions, including heart disease, high cholesterol, high blood pressure, diabetes, osteoporosis, and colon, skin, and lung cancer. Parents were given questionnaires including questions like if they would consider having their child tested. No children were actually tested in this study. Even though parents felt their children were in good health and were at low risk of developing the diseases in question, most would opt to have their child tested. Most parents felt that the perceived benefits of genetic testing outweighed the possible risks. They listed the benefits as knowledge, reassurance, and prevention. Whereas researchers had to educate them on the risks, such as invasion of privacy, psychological discomfort, and lack of proven clinical utility.

At present the National advisory groups and physician organizations caution against use of over-the-counter (OTC) tests for children. They warn that these tests are not meant to convey an individual's actual risk. Furthermore, these genetic tests are unregulated and have not been shown to have any clinical significance. These tests are available at drug stores and online, use large panels of gene variants that may be associated with an increased risk of common health conditions. However, they include so many genetic variants, that many individuals who are tested come back positive for at least one risk. Common health conditions, such as diabetes and high blood pressure are thought to have many causes, some of which are not yet known. Thus actual predictions might be difficult.

The authors advise that pediatricians should become aware of parents' interest in testing children and should be prepared to provide information and advice on the matter. “This is a new frontier for health care providers and for families,” says study author Kenneth P. Tercyak, associate professor of oncology and pediatrics at Georgetown Lombardi Comprehensive Cancer Center, a part of Georgetown University Medical Center in Washington, D.C. “It’s an open question on how they will be incorporated into a primary care setting.”

“This is not something that most pediatricians are trained for, and, frankly, it could be a huge problem,” says Marshall L. Summar, chief of genetics and metabolism at Children’s National Medical Center in Washington, D.C. “We’re trying to figure out how to gear up.”

Tercyak points out that other factors besides genetics must be weighed when considering a person’s risk for certain diseases. “The environment can be more important than genes,” he says. “Disentangling the two over the life course is still a puzzle.”

Summar, who was not involved in the study, predicts that over the next five to 10 years, the number of available tests will increase dramatically. He also says that over that same period their validity will likely become much better established. Until then, at least, he is not advising parents to make use of them. “Parents want the best things for their children,” Summar says, “but these tests are not yet at a level where they can address the health of their children.”

Dr Vivienne Nathanson, director of BMA Professional Activities, said, “We would have concerns about genetic testing being widely available over the internet or off the shelf because parents could find out results without a health professional to help intepret them. They may also find out about genetic abnormalities for which there are no cures, or be caused needless worry. It is important that parents who find out that their children have a genetic disposition to a particular illness, have counselling in advance so they understand the consequences of the test for their child, other children and themselves.”

Prof Tercyak said, “The findings of our study should remind clinicians and policy-makers to consider children when regulating genetic tests.”