High-Functioning Autism (HFA) - also called Asperger's - is a condition on the spectrum of autism disorders that most individuals associate with kids and adolescents, but I have a lot of clients who are (a) grown-ups with HFA, (b) spouses with an HFA partner, and (c) grown kids who have an HFA parent.
I believe the disorder is widely undiagnosed. In many cases, it doesn't come to light until a spouse or young adult seeks therapy for depression or poor self-esteem that results from the coldness and egocentricity HFA grown-ups demonstrate in relationships.
The criteria for HFA are "qualitative impairments in social interaction," which may include poor eye-to-eye gaze, failure to develop relationships and lack of "emotional reciprocity." The disorder also is marked by "restricted repetitive and stereotyped" behavior, such as inflexible adherence to routine, hand flapping or twisting and an abnormal preoccupation with certain interests.
Like other conditions on the autism spectrum, HFA is believed to be caused primarily by errant genes, and it is not typically associated with low IQ. Although there's no consensus on prevalence, a study in Journal of the American Academy of Youngster and Adolescent Psychiatry pins it at 1 in 400 among 8-year-olds, more often in boys than girls.
Though professionals use the same diagnostic criteria, interpretations make for wide disparities in diagnosis. Some individuals may have family members with autism spectrum disorders and exhibit features of HFA, such as "social deficits and a great deal of rigidities," but these traits are not tantamount to the diagnosable condition.
Experts who say HFA grown-ups don't marry or have kids either have their heads stuck in the sand or do not believe many of these individuals have learned to compensate for their deficits. Most HFA adults can – and do – learn how to compensate for their “problematic” symptoms/traits/behaviors. They are living with HFA and doing just fine.
Living With Aspergers: Help for Couples