Alright. What are the correlations with Gilgamesh, then?
I'd say a lot of the reason why people widespread believe in one and not the other is because a large portion of the bible is aimed at laying down a moral code and a codified way of life. On the other hand while the epic of Gilgamesh has some morals that get stated over the course of it, the majority of the story is simply that, a story.
Law 27: Play on people's need to believe to create a cult like following.
There's a reason why this exists; by giving a list of rules and various morals over its course, the bible is much better at "capturing" converts than the epic of Gilgamesh is. This ensures that even though some people may leave the religion, it can sustain itself by converting people from other religions.
In a lot of ways the study of memes and religions is very similar to that of evolution, funnily enough.
Those religions that are best at "spreading" through converts, are good at "surviving" by keeping those that join them present in the religion, and are good at "evolving" by having flexible enough moral codes to allow them to change over time to fit modern values are going to be those that survive the best in a given area, just as how the organisms that are best at spreading, surviving, and evolving are going to be the most widespread ones in biology.
As anecdotal hearsay however the bible is inadmissible as evidence to both scientific inquiry and legal proceedings
Honestly I'd say the biggest problem the bible has from a scientific point of view is a lack of both repeatability (from an experimental point of view) and a lack of supporting evidence (from a historical one). Compared to something like say, ice melting at 100 degrees, the miracles in the bible can't be recreated by people. And compared to something like say, the migration of people over the land bridge from Siberia over into the Americas, which has large amounts of physical evidence supporting it, something like the exodus of the Israelites out of Egypt, which has absolutely no physical supporting evidence, is lacking from a historical point of view.
From both sides it fails requirements to be able to be looked at either scientifically or historically on multiple counts. (Of course this says nothing about its philosophical or moral value, which can be taken seriously for discussion if needed).