Technology in Diagnostics: Is Autism Genetic?
Although the medical community’s knowledge about autism spectrum disorder (ASD) has grown by leaps and bounds in recent years, there remains a lot of research to be done. One of the areas with the most promise for emerging ASD research is genetics, science tech and the link between our genes and autism.
Is there a genetic test for autism? In spite of the well-established link between certain genetic mutations and ASD, there is no genetic test to detect or diagnose autism at this time. Why? Because not everyone with the gene mutations linked to autism ultimately develops ASD. For example, one genetic variance known to cause autism is the absence of 16p11.2, a stretch of chromosome 16. However, only about one in four people who are missing 16p11.2 are actually on the spectrum.
Should people with ASD undergo genetic testing? Since there’s a known link between many gene mutations and ASD, should people on the spectrum have genetic testing done? It’s a personal choice, obviously, but one that’s definitely worth considering.
First, it’s important to understand that, even if genetic tests reveal a mutation that’s linked to the individual’s autism, this won’t directly impact the treatment plan or outlook of the condition. As of now, there are no medications tailored to treating particular autism-linked mutations and there is no cure for ASD, even if the genetic cause is identified. However, some of the gene mutations linked to autism are frequently linked to other health issues, including epilepsy, kidney problems, or obesity, and arming yourself with the knowledge of the mutation’s existence can prepare people with ASD and their caregivers for other health issues.
How common are genetic tests for autism? Even though genetic tests can reveal useful information for people on the spectrum, most never get the opportunity to take advantage of them. In the United States, for example, only about one in three children with autism is even offered genetic tests. In some countries, like the United Kingdom and France, more children with autism are offered genetic tests, but in others, including Austria and many countries lacking the resources to offer genetic testing for autism, the numbers are much lower.
What genetic tests are available for people with autism? There are four main types of genetic tests used for individuals with autism: Karyotyping, which involves inspecting chromosomes under a microscope; chromosomal microarray analysis, which identifies duplicated or deleted DNA too small to show up on a karyotype; sequencing tests, which scan for mutations across single genes; and exome sequencing, which can be done for the patient and one or both of their parents to identify spontaneous mutations in the child’s genes.
Each kind of genetic test has its own strengths and weaknesses and not all are covered by insurance. Anyone interested in genetic testing related to ASD should talk to their doctor about the available options to determine the best fit.