When I was a clinical genetic counselor, each patient that I met with for genetic counseling had some different questions about how their positive genetic test results could impact their care or that of their family members. A common theme among patients who had children was that they wanted to know if, when, and how their children should be tested for the genetic mutation that was identified on their testing. Depending on the age of the patient’s children, and the hereditary cancer syndrome that we were discussing, my answers would vary. In this post, I want to give you a general overview regarding genetic testing of young children (< 18 years old) for hereditary cancer.

In general, genetic testing for hereditary cancer is not recommended for children under the age of 18, unless the particular condition is linked to an increased risk for childhood cancers. For many genes, such as BRCA1 and BRCA2, the increased risk for cancer is in adulthood, and there is not reliable evidence telling us that young children with mutations in these genes would have a higher chance of developing cancer. Here are a few of many things to consider when wondering why genetic testing of these genes is not recommended for young children:

• No known medical benefit: This is probably the most significant reason. A child who tests positive for a genetic mutation would not be recommended to undergo any screening or preventive surgery until older ages, like in their 20s-30s, so there is really no medical need to know the results at a younger age.
• Emotional distress for parents: If the child does test positive, but there is no screening or change in their care, this may cause emotional distress for parents, who could potentially feel helpless or guilty about the results.
• Emotional distress for children: If a child is tested before they can understand the testing and results, this may potentially cause emotional stress for them as they get older and begin to learn more and understand their risk for cancer. If they are old enough to understand their risks, then they may also feel helpless or concerned about the lack of screening options. For example, if a teenage girl is tested and learns that she is at an increased risk for breast cancer, then she may want to undergo breast cancer screening, but in most cases, this would not be recommended (or covered by insurance) until she is in her 20s, and this may be emotionally difficult for her.
• Child’s right to choose as an adult: Remember that each adult thinks differently about whether or not genetic testing is the right thing for them to do, and even about the timing of when they would want to know this information. If a child is tested at a young age, they are not able to make this choice as an adult, and this may be a concern for some people.

Remember that the information here does not apply to every gene and every hereditary cancer syndrome. There are guidelines available for healthcare providers to help determine when genetic testing for hereditary cancer is appropriate in young children. There are some genes that are linked to an increased risk for childhood cancer and have screening options available.  In these cases, it may be recommended for children, even as young as toddlers, to be tested. This decision, of course, may not be an easy one, and it is left up to the parents to determine if they want their child to be tested and at what age. If a child tests positive for this type of hereditary cancer syndrome, then there may be the medical benefit of increased cancer screening in childhood, or possibly options for prevention, which is why the testing is considered. You should talk to your healthcare provider about your genetic mutation (or the one that was identified in your family) to find out more about testing recommendations for young children, and if this is something that you should consider. If you plan to pursue genetic testing for your children, you may even wish to consider talking to a genetic counselor to discuss the potential implications of the testing before proceeding.