system
Given the following post, respond as if you're commenting on Reddit:
human
[Prometheus] if Engineer DNA is an "exact match" for ours why aren't we giants with white skin and black eyes?

Does "exact match" mean something different in this context?
gpt
The Engineers weren't an "Exact Match". The good doctor was very mistaken and looking at a protein sequence, not a DNA sequence.

This mistake was not caught because everyone on the Prometheus mission was severely brain damaged.

Truth is nobody had been in cryo that long before, and there were a number of unanticipated complications. The David unit suffered a partial dissolution of its' neural network due to prolonged uptime with no human contact.