IIRC, every ghoul in FO1 was from Vault 12; and I'd say it was meant to be an isolated event.
Doesn't make too much sense though (imo).
I mean, what makes 12 so much more special that only it's inhabitants became ghouls?
And if so, what are the requirements for creating ghouls?
Trogs for example has a formula:
* A couple of hundred rednecks
* Throw them in a cave
* Let radiation seep in over the course of generations
= Trogs.
So what made V12 so special that originally only "it" could create ghouls?
All it had was a door that weren't meant to close down.
So wouldn't people outside of vaults all over the world have turned into ghouls?
To further explain this:
Pitt Trogs can only be created at The Pitt.
They're an isolated mutation.
Swamp/hillfolk can only be created at places infected with the red plauge and large doses of radiation.
They're isolated mutations.
Lobotomites can only be created at Big Empty (speculation but I'm fairly sure this will turn out to be true.)
They're an isolated experiement.
Super Mutants can only be created by being dipped/gassed in FEV.
They're isolated mutations. (That have spread out after Unity's defeat.)
And Ghosts can only be created at the Sierra Madre due to it's mutagenic gas and suits that cause a symbiotic relationship between the wearer and the suit.
They're an isolated mutation.
So what used to make the V12 ghouls so special?
All I can see is that they got splashed with radiation.
Radiation is everywhere.
So why should the original ghoul design be isolated to V12 survivors exclusively?