Mutate is a term used to refer to superhumans who acquired their superpowers by exposure to some mutagenic compound or energy (either accidentally or deliberately). Unlike Marvel's Mutants, Marvel's Mutates require external stimuli to acquire their powers (i.e. they weren't born with the potential to manifest powers). Within the Earth X universe, the powers and abilities of Earth's Mutates and Mutants alike are the direct result of the genetic manipulations of the Celestials in humanity's distant past, who placed dormant genes within one cross-section of humanity, and the active Deviant and Eternal genes in other cross-sections.
Some humans have been altered by exposure to Terrigen Mists. Terrigenesis was previously used by the Inhuman race.
Deadpool fits into this category as he gained his healing factor from genetic alteration from the Weapon-X program (derived from Wolverine's).
On the island nation of Genosha, mutants who were discovered by the government were often genetically altered by the Genegineer into nearly mindless slaves known as Mutates. These Genoshan mutates were permanently sealed into "skinsuits" which recycled bodily wastes into nutrition and prevented sexual contact, and when not working were kept in a concentration camp out of sight of the public. Though these "mutates" started as mutants, they are considered mutates due to the outside alteration of their abilities; for example, the mutate Jennifer Ransome's genetic potential was for healing, but the Genegineer altered her ability to shaping rock and metal rather than flesh, and granted her superhuman strength and durability in the process.
A few other famous Marvel superheroes are also sometimes controversially included in the "mutate" category, e.g. Ant-Man/Giant Man (permanently mutated by prolonged absorption of "Pym particles") and Captain America (altered by the super-soldier serum, the results of which have sometimes been attributed to genetic alteration, and in other storylines have been described as a symbiotic prion-like substance or organism replicating in each cell in his body.)
In the post M-day, Forge created a team of “New Mutants” by artificially bonding functioning X-genes to the chromosomes of test subjects. Side effects included noticeable decline of the cognitive abilities of the test subjects.
Mutates differ from "normal" people in the way their bodies respond to the mutagenic influence. While most people would die from gamma radiation (The Incredible Hulk #296), people like Hulk and the Abomination become transformed instead. Exceptions occur in more controlled forms such as genetic engineering.
The term "Mutates" has also been used by the Deviants to refer to those of their race who are considered too severely deformed or otherwise not believed genetically suitable for reproduction. These Deviant Mutates are often sentenced to fight to the death in gladiator arenas for the amusement of the Deviant populace.[volume & issue needed]