It hasn’t, as of the date of this publication, been proven that Asperger’s is genetic. However, Asperger’s has shown to have a higher occurrence between siblings and cousins in the same family. Some undiagnosed parents have had children who were then later diagnosed alongside their parents as having Asperger’s. These occurrences have pointed to the possibility that Asperger’s is genetic, and genetic testing research has been and still is being conducted on families where Asperger’s appears to have a genetic link.
No test has been able to find a chromosomal link to Asperger’s either. Strands of DNA have been mapped out for many diseases and disorders already, but Asperger’s hasn’t been located to sit anywhere on the double helix, at least not yet. Scientists are hoping that by first finding the genetic connection between family members they can then turn their attention to the position of Asperger’s on the DNA strands. If it’s found to be passed, as theorized, from father to son or daughter, like balding, scientists can then look for it among the Y chromosomes. Because girls are also diagnosed, more rarely, with Asperger’s, this probably is A) not the place to look for it, or B) all girls with Asperger’s are being misdiagnosed.
You can see then, how complicated this gets the more research is done. The opposite could also be the area to look. X chromosomes exist in both male and female children. Prior to eight weeks conception, everyone starts their life as a girl. Something triggers an influx of testosterone, washing over the fetus and transforming it from girl to boy. Half the X chromosomes the fetus started with are destroyed and replaced with Y chromosomes. If Asperger’s occurs from environmental toxins being introduced at the same time, the X chromosomes are left alone and the Y chromosomes are affected in the midst of their transformation. This is another “genetic” theory suggesting that Asperger’s is in part passed down through the mother’s bloodlines and in part accidental introduction of toxins at a critical point of fetal development. It also explains why a few girls receive the diagnosis of Asperger’s too.
Scientists have to narrow their field of research and focus on one area over a set period of years. Narrowing the focus on one genetic theory helps to establish the control parameters so the data collected is sound. Several of these exact same studies with the exact same parameters have to be conducted to rule out any anomalies that occur during the research. Only then are the results proved conclusive, and a firm affirmation that Asperger’s has a genetic connection can be loudly proclaimed. You can see how the researchers in each of these areas of Asperger’s genetic theories would have a very difficult time trying to find the definitive answer for this question, and why it takes them so long to give the families and children with Asperger’s a solid answer.
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