several scifi franchises have shown both the positives and negatives of Genetic engineering

Star Trek for example

The Doctors in all series after the original regularly cure problem with gene therapy or dna altering compounds

Equally there are a lot of episodes involving Engineered diseases or even "Super" soldiers (ie Khan)

now it is true you don't see many Scifi franchises treat GE as anything other than a Pandora's Box but that is primarily due to the consumers knowledge of the subject - most people know enough to see the obvious pit falls (super soldiers, super diseases etc) without seeing the immense benefits that can also come with it - and the authors play to their audience