What is Genetic Health Testing?
Genetic health testing investigates an individual’s DNA, to identify genetic mutations or chromosomal changes that might trigger a rare disease in themselves or their future offspring.
The types of genetic health testing
Diagnosis of a rare disease or syndrome
Genetic testing can identify gene and/or chromosomal changes in a person’s DNA that might lead to a diagnosis of a specific rare disease. This type of genetic health testing can take place before an individual is born, during pregnancy, or after. It can also be carried out at any stage of a person’s life.
This form of genetic testing might identify a clear diagnosis of a rare disease, or it might identify a person’s potential risk for developing a genetic syndrome, based on their DNA changes. Sometimes a gene mutation puts an individual at greater risk for specific diseases or symptoms, breast cancer, for example, and understanding this mutation through genetic health testing can help with prevention, and early intervention.
Carrier screening is a type of genetic health testing to identify if an individual carries a gene mutation that might cause a rare disease in their future child or children, depending on how the mutation is inherited and passed on.
Carrier screening helps individuals understand more about their own genetic health, and how their genetic health might impact on that of their future children.
When might genetic health testing be recommended?
An individual with a family history of a gene mutation (carriers) or a diagnosed rare disease, will often be referred for genetic health testing. This will help them to understand and evaluate, as well as manage, their own possible risk for developing or passing on a rare disease.
Parent is a known carrier
Individuals who are known carriers of a gene mutation or change will need to plan a pregnancy very careful. Genetic testing of their partner, and their status as a carrier, will impact on how a pregnancy is planned. It is advisable for someone whose partner is a known carrier to also undergo carrier screening.
Infants, both prenatal and postnatal, born to one or more parents who are carriers of a genetic mutation, should undergo genetic health testing. This will confirm if the child carries the genetic mutation at all, and is so whether they do so as a carrier, or as someone with the specific rare disease or genetic syndrome that the change triggers.
Individuals who present with unique sets of symptoms, or even just more than one characteristic symptom, may be sent for genetic health testing. If symptoms have no other explainable or medical cause, then genetic testing might be advised, either to rule out or confirm a rare disease.
Genetic testing should provide a more comprehensive and accurate diagnosis, than relying on a diagnosis from the physical assessment of symptoms alone.
Before or during pregnancy
There are different genetic tests currently available for pregnant women looking to understand more about their child’s future health. Some of these are a standard part of pregnancy care in the developed world, specifically for down syndrome for example, but the development of new tests, including non-invasive procedures, are able to test for a wider range of rare diseases and syndromes.
These testing options are now available for pregnant women, whether they themselves are carriers, or considered more at risk for having a child with a rare disease. Generally, genetic testing is still recommended primarily for those of an older maternal age, as this can be a potential risk factor for spontaneous gene mutations and some specific syndromes.
The importance of genetic counseling
Genetic health testing, and its results, can be a difficult process. A diagnosis of a rare disease, or carrier status, is a life changing and altering event. It can be stressful, and emotional, and individuals undergoing genetic testing need access to the right information and support before undergoing the diagnosis process. This is where genetic counseling comes in.
Genetic counseling is an essential service for anyone thinking about embarking on genetic testing. It is able to explain the different types of genetic testing available, what each type of test involves (be it testing blood, or something more invasive), and what the potential results of the testing might be. Genetic counseling can also help an individual understand which type of test is the right one for them, based on their own and their family’s medical history.
Genetic counseling makes sense of the medical terms and jargon that surround the process of genetic testing, and it helps develop cooperation between all of those involved in the process, including all of the medical staff and genetic experts.
Crucially, genetic counseling is there to support an individual if their genetic testing confirms that they are a carrier, or if they have a rare disease diagnosis. It can help an individual understand more about their genetic health, and any options for treatment, and support. It can also help them understand their future family planning.
Importantly, genetic counseling offers essential emotional support during the entire genetic testing and diagnosis process. And when it comes to genetic health testing, genetic counseling is an indispensable part of the process.