Autism Diagnostic Criteria Needs to Be Adjusted for People with Genetic Conditions, Study Shows

Diagnostic criteria for autism has changed slightly over the years as experts learn more about the condition and the way it manifests in different people. But a recent study suggests that not enough has been done to understand how the disease shows itself in people with certain genetic conditions.

People with genetic conditions deserve to get their autism diagnoses and be able to move on with their lives and get the care and help they seek for their autism, but many of them don’t. This is because autism often shows up differently in people who have comorbid disorders coexisting alongside their autism.

The study, conducted by researchers at Cardiff University, suggests that more than half of people with one of four genetic conditions had significant autism symptoms but did not qualify for an official diagnosis. The four genetic conditions studied are 22q11.2 deletion, 22q11.2 duplication, 16p11.2 deletion, and 16p11.2 duplication, which are all grouped under the umbrella category known as “copy number variants” (CNVs).

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CNVs occur when a small section of a person’s DNA is either missing or duplicated. These disorders can be inherited but can also occur randomly, and many of them have been associated with a variety of health and developmental issues, many of which are not visible.

The study data show that people with CNVs are more likely to get autism than those without the conditions. In the individuals who participated in the study, anywhere from 23 to 58 percent were believed to have autism, depending on which genetic variant they had. These numbers are much higher than in the general population.

The research team also found that 54 percent of those people who had a CNV and did not meet all the criteria necessary for an autism diagnosis did exhibit significant autism symptoms. There was a considerable variability noted between the types of autism symptoms present in each patient, even between those with the same type of genetic condition.

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“Our study shows that an individualised approach is needed when assessing the needs of people with genetic conditions,” says Dr. Samuel Chawner, based at Cardiff University’s MRC Centre for Neuropsychiatric Genetics and Genomics. “Although many of those who were included in this study would not have met all of the criteria which define someone as having autism, more than half of those with these genetic conditions had significant symptoms associated with it—such as social and communication difficulties or repetitive behaviours.”

The researchers believe the method of diagnosing people with autism in clinical scenarios needs to be changed, particularly where these individuals are concerned. Just because someone does not meet all the criteria for an autism diagnosis, in other words, doesn’t mean that they don’t have autism spectrum disorder; it only means that the disorder manifests differently in certain people.

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“There is a danger that being too prescriptive with how autism is diagnosed will result in these individuals slipping through the net and being denied important services,” continues Dr. Chawner. “Sadly, many families we have met through doing this research describe longstanding struggles in accessing autism support for their child. This is often due to a lack of integration between genetic testing services and autism diagnosis services.

“Low awareness of genetic conditions can also be a barrier. It is important that clinicians are aware of the risk of autism associated with certain genetic conditions in order to improve opportunities for early diagnosis and support.”

More research will be necessary to corroborate these findings, but this is a big step forward for people with genetic conditions, and really all people who exhibit autism symptoms but have had a hard time getting an autism diagnosis. Here’s to a brighter future, where everyone will get the diagnoses, treatment, and support they deserve!

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