Sci-Fi, (Horror?). Alien Mutation, someone's body transforms into an alien (reptilian?) due to a virus. Read around 1997-2007. Spoiler ahead.

[Greg]

Read maybe 15-25 years ago.
The plot consist of someones body transforming into an alien (of the reptilian variety?) due to a virus that was dormant (in a mosquito in amber?)

It turns out that it is the way for the aliens to colonize worlds. The aliens were responsible for the disappearance of dinosaurs, as they were not "compatible" for the mutation, and to clean the slate for new, potentially compatible, species to emerge. By the end, the person psychologically embraced the mutation fully and there is a Stargate being build by the mutated for the alien invasion (Maybe not successful?)

[Greg]

sadly not

[Kris]

Greg, is this book for adults or teens?

Can you describe the main character - e.g., gender, age, job or student, where they live, etc.?

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