Continuing our series on types of DNA testing:
Knowing that a child has a genetic or inherited condition may improve treatment and access to helpful services for the family.
Why might knowing whether a child has a genetic condition matter?
Knowing that a child has a genetic condition may allow better treatment of the disease. For example, the child’s pediatrician might order different blood tests or studies like ultrasound or MRI to detect problems that could be treated with medication or surgery Other times, a diagnosis will give a child access to special medical or educational services like physical therapy or speech therapy.
How would you know whether a child might have a genetic condition?
Typical signs of an inherited syndrome might be:
-physical birth defect like a heart, limb, or brain malformation
-delays in learning to walk or talk
-intellectual disability or mental retardation
-autism or serious learning problems
-unusual growth pattern like very tall or short
-disabilities like blindness or deafness
What types of genetic tests are appropriate for children who might have a genetic disorder?
There are three broad classes of genetic tests for children.
1. A test for an individual syndrome - Sometimes a child’s symptoms strongly suggest a particular syndrome, even enough to make a diagnosis. In those cases, testing for that specific syndrome first might make sense.
2. A “gene panel”, which tests for different but related diseases - If a child has a heart defect, for example, a number of genetic conditions might be suspected. Testing for all of them at once may allow for cost and time savings. These panel tests are available for symptoms like skin, kidney, heart, eye, and other problems.
3. A broad test for many genetic conditions - Sometimes a child’s symptoms cross multiple medical specialties or do not suggest a particular condition. Other times, initial DNA testing for specific conditions does not identify a cause. In that case, the answer might come from studying more of a child’s DNA. Examples are whole exome sequencing or whole genome sequencing. Labs offering whole exome or genome sequencing consider the symptoms a child has and match them to huge databases of DNA findings.
How do parents get DNA testing for their children?
A specialist like a medical geneticist should evaluate the child first. Some other specialists who could be involved are pediatric neurologists or developmental pediatricians.