All mutants have a genetic mutation called an X-Gene that causes their bodies to develop abilities that regular humans, homo sapiens, are unable to. The majority of mutants develop these abilities, which vary from person to person, usually upon puberty, though there are some mutants who display powers and/or physical mutations from birth, or in their twenties. Some mutants even display abilities from within the womb and posthumously, like Professor Charles Xavier and Jean Grey, respectively.
Mutant powers vary seemingly without limit. Examples of powers shared by many individuals include: telepathy, telekinesis, flight, energy projection, accelerated healing and enhanced physical strength, agility, or senses; all to variable limits. Mutation can also entail a minor to radical alteration in physical appearance from the normal human- wings, gills, a tail, fur, altered skin color, etc.
Mutant powers can grow and increase as the mutant grows and develops. Some powers remain latent until activated by severe stress, or remain unnoticed throughout the person's lifetime, while others are apparent immediately from birth. Some individuals have a secondary mutation which activates in adulthood. For some mutants, several years of self-discipline are needed before they can control their powers, while others never gain full control of their powers.
Mutants may be born to human or mutant parents, though the odds of a mutant birth are much better for the latter. Likewise, it is rare but possible for mutant parents to have human children, termed "baseline" by characters within the Marvel Universe. Some baseline humans are genetically predisposed towards having mutant descendants such as the Guthrie family (see Cannonball, Husk, and Icarus). Mutant children born to mutant parent(s) will not necessarily have the same power(s) as their parent(s), nor will they necessarily have the same power(s) as any mutant siblings they may have; however, examples of children with the same power(s) as their parents and/or siblings are not uncommon.
There is, however, a chance that mutants may not even be able to reproduce a child at all. The Hayes (Runaways), telepathic mutant doctors, were unsure their mutant heritage could even produce a child; it did, however, take them several years to finally have a child: Molly Hayes.
In the Marvel Universe, Secondary Mutation was a fictional worldwide phenomenon among mutants that seemed inexplicable, with many previously established mutant characters suddenly developing new or vastly expanded powers. Henry McCoy hypothesized that, since the mutant population was entering the millions at that time, mutant physiology was responding to the need for survival. Thus in rare occasions a mutant's powers change or become even greater, and in rare cases they can develop a new, often unrelated ability. However, the criteria for secondary mutation is ill-defined at best, leaving many fans confused as to their favorite character's status or powers. This use of secondary mutations can sometimes be misused as a Deus ex machina; if the writer can't think of a way for a character to get out of a situation, they can simply develop a spontaneous new power to handle the problem.
An Omega-level mutant is one with the most powerful genetic potential of their mutant abilities. The term was first seen in the 1986 issue Uncanny X-Men #207, but was completely unexplained (beyond the obvious implication of it referring to an exceptional level of power). The term was not seen again until the 2001 limited series X-Men Forever. Some abilities depicted by mutants described as Omega-level include immortality, extreme manipulation of matter and energy, high psionic ability, strong telekinesis, and the potential to exist beyond the boundaries of the known physical universe. No firm definition has been offered in comics. Mutants that have been confirmed as Omega-level include Jean Grey, Iceman and Legion.
Mutants and Disease
Mutants are immune to the AIDS virus as revealed in an issue of Uncanny X-Men in which the character Archangel discussed he did not need an HIV test due to his status as a mutant. Before its elimination, mutants were particularly susceptible to the Legacy Virus. Mutants are also born with a natural immunity against certain other genetic infections like Phalanx and Sublime, and a specific brainwave pattern that can be detected by certain means, such as the Cerebro device.
Created by Rob Liefeld, Externals are immortal mutants. Eventually, most of the Externals were killed by the Selene, thus proving that they were not so immortal after all. Gideon, Selene, Candra, and Apocalypse are examples of Externals.
Introduced in the second series of X-Factor, a changeling is a mutant whose powers manifest at birth. Jamie Madrox AKA the Multiple Man and Damian Tryp are examples of this sub-class. Catseye or Blindfold may be as well, as they were mutated at birth.
Maximus Lobo claimed to be a part of a mutant sub-species of feral, wolf-like mutants, whom he called The Dominant Species. He later tried to recruit Wolf Cub into his ranks, to no avail. A few years later, another mutant, Romulus claimed that some humans evolved from canines instead of primates. Mutants who were a part of this group were Romulus, Wolverine, Daken, Sabretooth, Wolfsbane, Wild Child, Thornn, and also Sasquatch. These groups appear to be one and the same.
The term "mutant" in the Marvel Universe does not apply to those whose DNA has been mutated by an external force; in such case, those individuals are called mutates. The genetic material of mutates has been altered by an outside stimulus such as radiation, toxic shock, chemical agents, or energy. Spider-Man, who was not born a mutant, but was granted super-human powers by the bite of a radioactive spider, which injected irradiated spider venom into his bloodstream, is a popular example of a mutate.
Some mutates have been altered by magic, such as Juggernaut. These individuals were given the name magic-based mutates as of Civil War: Battle Damage Report.
Following the events of House of M many mutants have lost their powers - or, more specifically, their X-genes - and become physically human. In Son of M, several ex-mutants are exposed to the mutagenic Terrigen Mist, in some cases restoring their powers in uncontrollable forms but in others, such as Quicksilver's, granting entirely new powers. All, however, are now technically mutates, not mutants.
A fact that's generally overlooked is that many mutants are also mutates. John Wraith and David North were born genetic mutants who later were giving healing factors by Weapon X. Apocalypse has enhanced various mutants.
A March 1952 story in Amazing Detective Cases #11 called "The Weird Woman" tells of a woman describing herself as a mutant who seeks a similarly superhuman mate.
A character with superhuman powers, born from a radiation-exposed parent, was seen in "The Man With The Atomic Brain!" in Journey into Mystery #52 in May 1959; although not specifically called a "mutant", his origin is consistent with one.
A little-known story in Tales of Suspense #6 (November 1959) titled "The Mutants and Me!" was one of the first Marvel (then known as Atlas) stories to feature a named "mutant".
The modern concept of mutants as an independent subspecies was created and utilized by Marvel editor/writer Stan Lee in the early 1960s, as a means to create a large number of superheroes and villains without having to think of a separate origin for each one. As part of the concept, Lee decided that these mutant teenagers should, like ordinary ones, attend school in order to better cope with the world, in this case Xavier's School for Gifted Youngsters. These mutants first appeared in the superhero series X-Men, which debuted in 1963 and remains the most prominent vehicle for the mutant concept.
The extensive popularity of the X-Men led Marvel to create several additional mutant superhero teams, including The New Mutants, X-Factor, Excalibur, X-Force, and Generation X.
Officially, Namor the Sub-Mariner is considered the first mutant superhero whom Marvel Comics ever published, debuting in 1939. However, Namor was not actually described as a mutant until decades after his first appearance. The same is true of Toro, a little-known hero introduced in 1940 (later revealed to be an Inhuman descendant).
One million years ago, an alien race called the Celestials came to Earth and performed genetic experiments on proto-humanity, incorporating and altering DNA in the genetic code of the early species of the genus Homo to allow future generations to gain superpowers, making the Celestials the source of all mutants.
The first mutants
The first recorded mutant on Earth is Selene Gallio (active as early as the Hyborian Age); as her particular mutant powers grant her immortality, however, she may not necessarily be the first mutant. Given the character's propensity for lying and misleading, it is also possible that she fabricates this element of her biography. She was considered a de facto member of the Externals, a defunct group of ancient immortal mutants. Apocalypse, born in the 30th century BC, is often referred to as the first mutant. Gateway is another noteworthy ancient mutant.
Some of the first mutants were honored as gods, like Selene herself.
Cheyarafim and Neyaphem
The Cheyarafim and the Neyaphem are two species of mutants in comic books by Marvel Comics. They first appear in biblical times. According to the character Azazel, the Cheyarafim are a group of angel-like mutants who were the traditional enemies of the Neyaphem, a demonic-looking group of mutants who lived in Biblical times. The Cheyarafim were fanatics who had a strict, black-and-white view of morality which led them into conflict with the Neyaphem. This escalated into a holy war, causing the Neyaphem to be exiled into an alternate dimension. What happened to the Cheyarafim after this has not been revealed. The X-Man Angel is said to be a Cheyarafim, while Nightcrawler is a Neyaphem.
Post-World War II
Very few people know about mutants before the latter half of the 20th century. Given that mutants were an unknown population until after World War II, many, if not the vast majority of mutants apparently hid their powers. The general public did know about mutates, however, like Captain America. The American military knew of Wolverine, but they were unaware that he was something categorically different from other supersoldiers.
Prejudice against mutants
It is unclear within the Marvel Universe when, exactly, mutants were exposed to the world. Activities of some superheroes and supervillians may have been what notified the general public about the existence of mutants.
Many people harbor prejudicial attitudes about mutant people. They do so for a variety of reasons, including bigotry and xenophobia (particularly directed at mutants with nonstandard appearances), jealousy of their natural superpowers, and fear of being replaced or rendered extinct by the so-called next stage in human evolution. Anti-mutant sentiment often leads to mob violence and the alienation of mutants from society. Mutant Town, for example, is a ghetto-like neighborhood in New York City.
By comparison, most non-mutant superheroes, including mutates, are not affected by such bigotry, example: Fantasic Four, Ms.Marvel, Spider-Man, etc. Occasionally such people, such as Howard the Duck, are mistaken for mutants and treated accordingly.
Some media outlets go against the current of anti-mutant sentiment, most notably the Daily Bugle, which under publisher J. Jonah Jameson has repeatedly advocated in favor of mutant rights and causes. Just as the X-Men themselves are targeted by mutant extremists, human hate groups like the Friends of Humanity have been known to attack humans who are mutant sympathizers.
The X-Men and Mutant Supremacists
As many people hate mutants, their safety, wellbeing, and lives are jeopardized. The X-Men, founded by Professor Charles Xavier, are mutant superheroes who defend a world that hates and fears them and who work for peaceful mutant-human coexistence. They deal with anti-mutant sentiment, mutant exploitation, and a number of organized anti-mutant campaigns such as:
- Mutant-hunting robot Sentinels of Project: Wideawake and Operation: Zero Tolerance, both sponsored by the US government. Under Cassandra Nova, Sentinels killed approximately 16 million Mutants on Genosha (New X-Men #115 ['E' is for Extinction Storyline] , 2001).
- Weapon X, part of the larger Weapon Plus project, a covert program of the U.S. government.
- Friends of Humanity, perhaps the best-known and most infamous of the anti-mutant hate groups.
- Humanity's Last Stand, a similar anti-mutant survivalist group.
- The U-Men, a cult-like group who attempt to gain superpowers from mutant organ transplants
- The "Purifiers," a religious hate group led by Reverend William Stryker. Such groups are particularly inflamed by the fact that, by genetic coincidence, some mutants have an angelic or demonic appearance.
At the same time, they confront threats (to both mutants and humans) coming from mutants such as Magneto and Apocalypse, who (in their own ways) believe their species has a right to rule over ordinary humans, simply by virtue of being more genetically advanced. A considerable number of ordinary humans fear a potential mutant/human war, partially due to the actions of these mutants.
Some mutants have been important parts of such traditionally non-mutant teams as the Avengers, the Fantastic Four, and the Defenders, even receiving celebrity or iconic status as a result.