Science is based on "natural" causes and effects. What does "natural" mean in this context?
O Phenomena that can be reliably observed with senses or instruments; NOT
supernatural.
O Phenomena that occur on their own without being manipulated; NOT
controlled.
O Phenomena that occur without the direct participation of humans; NOT
artificial.

○Phenomena that occur on their own without being manipulated;Not controlled.

Explanation:

the word natural means which already existed in nature and not controlled by anyone or a thing, where the Phenomena that occur on their own without being manipulated; Not controlled.

"1. it should be, it has been for about 20 years, and it's really not much different in the end than breeding animals to have particular traits. there are always concerns about genetically engineered animals/plants affecting the environment in unexpected negative ways, but i can't think of an example where the fears didn't turn out to be baseless.  

first, as you point out, it would be a great advance in pharmacology, to be able to tailor drugs and their doses to me. the pros involve better medical treatment. the cons involve privacy issues like insurance companies denying coverage to people with genetic risk factors. looking at dna markers wouldn't affect the frequency of genetic diseases, but it would allow detection of them earlier. and ok, actually i suppose that if people used this information to avoid having children with genetic diseases, some might decrease in frequency."