Might the genetic factor be the only answer to asperger's syndrome?

Probably not: While genetics most certainly is a factor, it is very unlikely to be the only factor in all cases of asperger's. If you know someone with asperger's it may be that in their particular case genetics is the cause and the only cause, but you can't say that's what's going on in all cases. It's very likely that as we learn more about the syndrome, we'll find that most cases are due to the environment.

Aspergers and Genes: Actually. I think genetics is the definitive answer.

Unfortunately, no: Asperger and the whole autistic spectrum are not purely genetic, but have a genetic component. Geneticists can definitively say whether a particular trait follows laws of Mendelian genetics, and now can identify the mutations responsible. More than a half-dozen different genes contribute to autism, but there are also environmental factors, non-genetic, which trigger the condition.