Recent research has shown that it is a misconception from previous teachings that identical twins have identical DNA – they don’t. By definition they started out with the same DNA but either at, or shortly after the first cell division which created the two individuals there are some “replication errors” which make the two developing individuals “almost” identical. These “errors” may be a replication of a number of gene sequences (called Copy Number Variants – CNV’s) which do not dramatically alter the individual cells ability to develop to term in a systematic sense but may produce very small differences in utero development or later as the individual grows.
This is a discovery since the human genome was fully mapped, the reduction of cost and speed of DNA sequencing now allows individuals to determine slight differences in their own DNA and is offering researchers amazing new tools in the determination of the genetic aspects of ASD.
These slight differences may be very important in the understanding how the autistic condition is initiated but sadly very unlikely to lead to a short term treatment. If however when (and if) the mechanisms are fully understood (these are likely to be a complicated compound effect of multiple genes and control mechanisms) there may be biochemical interventions which alleviate symptoms and perhaps correct brain chemistry but well down the road.