DEAR MAYO CLINIC: What are the chances of Asperger syndrome being inherited?

ANSWER: Although doctors and researchers don't understand exactly what causes Asperger syndrome, there seems to be a strong genetic component associated with this disorder. For example, having one child in a family with Asperger syndrome significantly increases the risk of a second child in that family also having Asperger syndrome.

Asperger syndrome is a developmental disorder that affects a child's ability to socialize and communicate effectively with others. Children with Asperger syndrome typically exhibit social awkwardness and an all-absorbing interest in specific topics.

Signs and symptoms of Asperger syndrome often include engaging in one-sided, long-winded conversations; displaying unusual nonverbal communication, such as lack of eye contact, few facial expressions, or awkward body postures and gestures; showing an intense obsession with one or two specific, narrow subjects, such as baseball statistics, train schedules, weather or snakes; appearing not to understand, empathize with or be sensitive to others' feelings; and having a hard time reading other people or understanding humor.

Doctors group Asperger syndrome with other conditions that are called autism spectrum disorders or pervasive developmental disorders. These disorders all involve problems with social skills and communication. Asperger syndrome is generally thought to be at the milder end of this spectrum.

Research has shown that a child born to parents who already have one child with an autism spectrum disorder has approximately a 4 to 10 percent chance of also developing one of these disorders, including Asperger syndrome. In families without a history of autism spectrum disorders, the chance of having a child with one of these disorders is approximately 0.7 percent.

Although there appears to be a genetic component to Asperger syndrome, it's not the type of disorder that can be detected through genetic testing. This is because Asperger syndrome is a descriptive diagnosis. That means a child is diagnosed with Asperger syndrome based on the signs and symptoms he or she has, rather than results of a specific laboratory test.

In addition, unlike some disorders directly linked to genetics such as Down syndrome, there's no prenatal test to show if a fetus has Asperger syndrome. And, Asperger syndrome can be difficult to diagnose in infants because many of the behaviors associated with Asperger syndrome don't become obvious until a child nears school age or enters school.

If you have a family history of Asperger syndrome or another autism spectrum disorder and you're pregnant or recently have had a baby, talk to your doctor about signs and symptoms to watch for in your child. In particular, children born into families who already have one child with an autism spectrum disorder need to be closely monitored and their development tracked regularly. Then if signs and symptoms of these disorders do appear, effective intervention can begin as early as possible.

If you're concerned that your child is showing signs of Asperger syndrome, make an appointment to have your child evaluated by your pediatrician or family doctor. He or she may refer you to a developmental pediatrician, child neurologist or child psychiatrist for further evaluation. In addition, if your child is school-age, talk to school staff about assessments that are available to determine if your child is eligible for special education services.

-- Robert Voigt, M.D., Developmental and Behavioral Pediatrics, Mayo Clinic, Rochester, Minn.

Medical Edge from Mayo Clinic is an educational resource and doesn't replace regular medical care.

 

 

(c) 2009 Mayo Foundation for Medical Education and Research