Autism and Genetics
Is there a genetic test to diagnose autism?
This is a question many families have when they suspect their child may have autism. The simple answer is that there isn’t a genetic test to diagnose autism and, in fact, there isn’t a single gene for autism. There are, however, genetic conditions in which autism may be the very first medical or developmental symptom.
This is why multiple medical guidelines, including Amercian Academy of Pediatrics (AAP) and American College of Medical Genetics (ACMG), recommend genetic testing for all children with autism spectrum disorder or developmental delay.
Three medical reasons genetic testing is ordered by doctors
1. Genetic testing can give a definitive answer to why a child is behind in the developmental milestones. DiGeorge syndrome (also called 22q11.2 deletion syndrome), for example, is one of the many genetic conditions that can be identified by genetic testing.
2. A genetic diagnosis can help provide a roadmap for medical care and therapies that may be more impactful for individuals with that specific genetic condition. For example, children with DiGeorge syndrome need to be evaluated for internal birth defects such as heart and kidney issues that we otherwise wouldn’t be aware of.
3. A genetic diagnosis can help inform how other family members may be impacted. For example, one out of every 10 children with DiGeorge syndrome inherited the deletion from a parent who may not have known that he or she also had the condition. Other family members may have a recommended medical follow-up if an inherited condition is identified.
American Academy of Pediatrics (AAP) Moeschler JB, Shevell M; Committee on Genetics. Pediatrics. 2014 Sep;134(3):e903-18
The Professional Practice & Guidelines Committee of the American College of Medical Genetics (ACMG) Manning M, Hudgins L. 2010. Genet Med 12:742-745
The group formerly known as the International Standards for Cytogenomic Arrays Consortium (ISCA) Miller DT, Adam MP, Aradhya S, et al. 2010. AJHG 86:749-764
The Autism Consortium Clinical Genetics/DNA Diagnostics Collaboration Shen Y, Dies KA, Holm IA, et al. 2010. Pediatrics 125:e727-7350