The amount of knowledge in our genetic code is astounding. It tells us everything from what color of eyes you’ll have to whether you might be predisposed to developing breast cancer.
And while a lot of genetic testing is currently done to evaluate personal health risks, couples thinking about becoming parents have the option to screen for various genetic conditions that may affect their future children. Essentially, screening helps to estimate a couple’s chance for having a child with a genetic condition. It also provides family members with information they may have never known.
“Everyone is most likely a carrier for some genetic condition,” said Shelby Brown, a certified genetic counselor with Sanford Health. “Most carriers identified through carrier screening will not have associated health problems. However, when both parents are carriers for the same condition, the chance for having a child with a genetic condition greatly increases.”
Information from testing
While most people may be aware of conditions that run in the family, carrier testing allows parents to find out about the possibility of those 1 in 1 million situations.
“When you are mixing two sets of genes, anything can happen,” Brown said. “In these cases, knowledge can be power. If you discover you are both carriers for cystic fibrosis, a genetic condition that is common in the Caucasian population, options exist both preconceptionally and prenatally, and parents can use the information to make delivery plans, management plans or even future therapy plans.”
Carrier screening will screen for many different hereditary conditions. For some couples, this type of information can seem overwhelming or cause anxiety. So one of the first things a genetic counselor will do when talking about carrier testing is to ask what some of these conditions or knowledge of the screen results may mean to the couple. For example, is the couple concerned about a certain genetic condition? Or, if the couple were to find out they are carriers for the same condition, would their pregnancy management change?
“Carrier testing is a personal choice,” Brown said. “Before we start, we ask what the couple is looking to gain from it. There is such a broad range of information that can come from a genetic test that we want couples to have all the proper information in order to make an informed decision.”
The overall process for carrier screening is simple.
Couples will give either a blood or saliva sample at the clinic. These samples will then be sent to an outside laboratory to be analyzed and evaluated. Results typically take two to three weeks to get back. Then couples can again meet with a genetic counselor to go over the findings and risks for their future children.
Carrier screening can be completed in multiple stages. A couple can have carrier screening completed at the same time and receive their results together. Alternatively, one person can be screened first. They can then review the results, decide whether the information is helpful or concerning, and then decide whether the other partner should be screened.
“With these types of tests, there is never a zero percent chance or a 100 percent chance,” Brown said. “The test may show that the chance of having a child for a particular condition is greatly decreased, or that an increased risk does exist. Thus, genetic counselors can really help couples better understand and decide what they wish to do with the information.
“Overall, screening is a personal decision, but genetic counselors are available to help every step of the way.”
- Genetic testing reveals hereditary heart disease
- Cell-free DNA testing for Down syndrome explained
- What testing for birth defects can tell parents