If sunlight changes your DNA, can drugs, vaccines, food also do that?
This is what UV light does. It can trigger mutations locally, in the genetic makeup of your skin cells, and you then can get skin cancer. Essentially, what happens is if the anomaly remains in a specific gene that for example assists the cell control its proliferation, that cell may start dividing uncontrollably and a facilitate the growth of a tumour. I’ve over simplified of course but that is the basic idea.
Now. Could the chemicals you consume trigger such mutations too? Absolutely. You eat them? You get stomach cancer. You inhale them? You get lung cancer.
This tells us two things. The resulting disease is localized and it’s usually cancer.
This happens because most other disorders that have a hereditary basis only happen if there are several mutations and they are already present in the fertilized egg. But then, they’ll be present in every cell of the body. A lot of those conditions are rather complex, like autism, schizophrenia, bipolar illness and many genes need to be affected to cause these intricate disorders.
Now. For vaccines to cause autism it would be necessary for the components of the vaccine to get to the brain, and once they get there to cause mutations to a number of genes, all in the same cell, and in a number of different cell types on top of that. If that could take place, way more kids would get way more serious conditions from vaccination than autism (which is what fearmongers love). It does not take place though, due to the fact that the vaccine components won’t cross the blood brain barrier. They could enter into a lot of other organs though, so if they were cancerous or dangerous in some ways wouldn’t there be lots of different illness occurring after vaccination? And if that, especially cancers? It’s simple logic, really.