Though not mutants in the biological sense, these two comic book characters exist primarily in the Marvel Mutant Universe and primarily in that of The Wolverine.
Elsie-Dee was created, along with her partner, Albert by Donald Pierce, the same man who put together the team of the Reavers who waged war on Mutants and the Wolverine in particular. Pierce hates Mutants and hates himself as well for not completely being a man. He is part cyborg and part man. Pierce creates or enhances other cyborgs with the sole purpose of hunting and killing mutants. He creates the duo of Elsie-Dee and Albert to hunt and kill the Wolverine. Albert is a cyborg double of the Wolverine and looks exactly like Logan. Elsie-Dee has the appearance of a five year old child. Albert would lure the Wolverine into battle and inside Elsie-Dee is a bomb with sufficient force, they believe, to kill the Wolverine. But Elsie-Dee was given the maximum artificial intelligence possible and she decides she doesn’t want to sacrifice herself. She disarms the bomb inside of her and in battling with the Wolverine, Albert and Elsie-Dee find him to be of noble character and they counter-act their programming.
The two cyborgs fight alongside Wolverine on several occasions but eventually leave to have adventures of their own. They end up traveling back in time to the wilds of North America to fight alongside the local native Americans. There it seems they have stayed, happy to not be a part of battle between mutant and Reavers.