Marvel Database

Mutants (Homo superior) are distinguished from baseline humans (Humans (Homo sapiens)) by their mutant genes.

This page is about history, detection and classification of the mutant genes (or other factors of mutation).
For their functionment and effects, please consult the Mutant Biology page.



During their First Host on Earth, one million years ago,[1] the Celestials collected the Wanderers,[2] a tribe of Homo erectus.[3] Gammenon the Gatherer collected the ape-men and sent them to Ziran the Tester who mutated them to have an unstable genome, creating the Deviants[4] (Homo descendus),[5] a race with various mutations, who were then released and went hiding in the caves. With other subjects, Nezarr the Calculator then created the Eternals[4] (Eternals (Homo immortalis)),[1] hairless, upright tall beings able to tap into the cosmic power. They were themselves released, flying out of the Celestials' laboratory-ship. Finally, Oneg the Prober created a latent gene for the expansion of human potential and those modified yet apparently unchanged ape-men were released.[4]

The potential for superhuman powers was only latent:[6] That dormant "DNA complex"[7]/"mutant genes" implanted in Homo erectus.[3]

That potential was transferred to Homo antecessor,[8] then to Homo neanderthalensis, both species experimented on by the Kree in order to create the Inhumans (Inhomo supremis).[9]

It later came to fruition into the form of Homo superior, the mutants.[10]

First activations

A few X-Gene mutants occurred early in human history, with some controversy over the earliest. Included in those known early mutants are the Forever Man,[11][12] Garbha-Hsien,[13][14] Amahl Farouk,[15] Nicodemus,[16][17] and possibly Hungry.[18]

The first recorded (with a clear date) human mutant on Earth was Selene, born in Central Europe 17,000 years ago, "after the Oceans swallowed Atlantis" and "before the rise of the sons of Aryas".[19]

For years, it was thought that the mutants were only a handful individuals at the first stages of humanity.[20][21] That theory was proven wrong by the discovery, in 2003, of a mutant civilization at least 15,000 years old,[22] antagonists of the Cheyarafim, another early group of mutants.[23]

Egypt was later the birthplace-and-time of many mutants: The Man and others of his kind (named the same way),[24] En Sabah Nur and his Clan Akkaba, one incarnation of the Forever Man,[11] and Anath-Na Mut.[25]

Please consult the apparition and development of mutantkind here.


Despite those early mutants, around six to seven hundred years ago,[26] a population of three hundred "Proto-Mutants" (an "early" form of mutants with "less evolved" X-Genes), a different species from mutants, like Neanderthals to humans,[27] lived in mountains of Crimea.[28]

At the same period, another form of "early mutants", the "killcrops", was characterized by early appearance of powers, and allegedly leading the way to the modern mutants with puberty-induced mutation.[29]

Essex Factors

In 1859,[verification needed] Nathaniel Essex presented his work and theories on the Essex Factors, illustrated by a cadaver he pieced together from human and animal remains. He was rejected by the Royal Society of London. He then looked for "freaks" and was shown a collection of some of them by the Marauders[30] during his search for the ones with the Great Mutation, the right "Essex Factor", the "Essex Men".[30]

Modern discovery


Attempts at erasing it

Many attempts have been made to remove the X-Gene.


The X-Gene is the major gene mentioned when describing mutants.

The localization of the X-Gene changes from one universe to another, but also from one statement to another within the same universe.

On Chromosome 23

In Earth-616, Hank McCoy states they were set on the 23rd chromosome,[31] which appears to be the sexual chromosomes, or gonosomes (as there is in humans 22 pairs of regular chromosomes, or autosomes, and one pair of sexual chromosomes, X and Y).

Carried by female

Storm stated it was carried on the female genome, intending that the mother transmitted the gene for mutation.[32] In the alternate reality of Wolverine: The End, White Ghost states that Wolverine got his mutant gene from his mother Elizabeth. If this fact applies to the mainstream continuity, it has not yet been revealed.

Carried by male

A Wakandan scientist stated that Gentle's X-Gene originated from his father,[33] although that may simply have been a xenophobic statement, as his father was not Wakandan.

The case of X-23 proves that Wolverine's X-Gene is positioned at least on the X chromosome, as the Y chromosome her creators possessed wasn't usable and was replaced by the human X chromosome of Sarah Kinney (leading to a female "clone").[citation needed]

In Earth-10005, Pyro stated from his learning that it was the male who carried the mutant gene and transmitted them to their descendants.[34]

X-Factor chromosome

Odysseus Indigo talked about a "X-Factor chromosome".[35]

In Earth-688, Ben Parker was stated to possess an extra chromosome, a "variant X-Factor chromosome".[36]

Other mutant genes

Feral Gene

The feral gene (manifesting in animalistic mutations such as the ones of Feral or Sabretooth) is stated to be more common in mutants than other powers such as flight or telepathy.[37] See the list of characters stated to carry the feral gene.

M Gene

Another mutant gene listed apart from the X-Gene include the M Gene. It can also be activated by using radioactivity as a catalyst.[38]

Replicator Gene

The Replicator Gene allows individuals to duplicate another humanoid or near-humanoid so accurately that even those closest to them couldn't tell the difference. This gene extends to the reproduction of another individual powers.[39][verification needed]

No "Mutant Gene"? (Earth-58163)

In Earth-58163, it was stated by Dr. Henry McCoy that the "mutant gene wasn't a reality, that it wasn't "one stand of DNA [but] millions strung together. It's a combination so complex that it [wouldn't] be figured out in [his] lifetime."[40]

Although, it is possible that it is part of a lie to discourage attempts to duplicate it (the subject who led McCoy to that statement),[40] considering that Moira MacTaggert, the one who won a Nobel Prize for being the first to properly identity the mutant phenomenon and then tried to cure her son (sick by his mutation) "by isolatin' and neutralizin' the mutant gene itself.".[41] It could also be that Moira is wrong and the mutant gene doesn't exist in Earth-58163.

That can also be due to a lack of coordination between the authors.


A few ways exist to test people as mutants:

  • Looking for readings with Cerebro,[42]
  • Looking for the X-Gene (and possibly for altered DNA helix or hereditary markers,[42] although they are presumably not specific to mutants).
    • There more extensive tests that could be done, involving cellular search in bone marrow.[42]

In Earth-11326, X-Gene was proceeded in order to detect and arrest mutants.[43]

False negatives

On some cases, X-Gene testing at birth have revealed negative results for people actually proved to be mutant afterwards, such as Molly Hayes.[44]

In Earth-4935, similarly, Blaquesmith's genescan stated him to be X-Factor Negative and his appearance to be the result of a genetic defect and not an X-Factor mutation, but that test was seemingly wrong, as Blaquesmith exhibited a telepathic gift[45] (he was later confirmed to be a mutant).[46]

Recessive genes

One of the X-Ceptionals claimed as an explanation for his alleged unpowered mutant state that his mutant gene was recessive.[47]


  1. 1.0 1.1 Thor & Hercules: Encyclopaedia Mythologica #1
  2. X-Men Annual #13
  3. 3.0 3.1 Marvel Fact Files #8
  4. 4.0 4.1 4.2 What If? #23
  5. New Eternals: Apocalypse Now #1
  6. All-New Official Handbook of the Marvel Universe A to Z: Update #2; Panther God's entry
  7. Blackwulf #7;Godstalker talked about such DNA complex to mutant Sparrow
  8. Fantastic Four #577
  9. Inhumanity #1
  10. Blackwulf #8; Godstalker stated that Sparrow's kind (mutants) was the fruition of genetic experiment performed one million years
  11. 11.0 11.1 Avengers Assemble #1; Forever Man's entry
  12. Avengers #218
  13. X-Force #23
  14. X-Force #53
  15. X-Men: True Friends #2
  16. X-Force #10
  17. X-Force #20
  18. Wolverine: Weapon X Files #1
  19. X-Necrosha #1
  20. X-Men #1
  21. X-Men #60
  22. Uncanny X-Men #422
  23. Uncanny X-Men #433
  24. Journey into Mystery #40
  25. Marvel Encyclopedia #Fantastic Four
  26. X-Men (Vol. 3) #31: The DNA was estimated to 7 hundred years by Dr. Hunter
  27. X-Men Vol 3 #31
  28. X-Men Vol 3 #32
  29. X-Factor Vol 3 #10
  30. 30.0 30.1 Further Adventures of Cyclops and Phoenix #1
  31. Astonishing X-Men Vol 3 #25
  32. Black Panther Vol 4 #17
  33. X-Men Divided We Stand #1
  34. X2 (film)
  35. X-Force #86
  36. What If...? #88
  37. Wolverine Vol 2 #312
  38. Spectacular Spider-Man Vol 2 #19
  39. X-Force #126-128
  40. 40.0 40.1 Secrets of the House of M #1
  41. Exiles #70
  42. 42.0 42.1 42.2 Cloak and Dagger Vol 4 #1
  43. Age of X Communiques: Basilisk, Legacy
  44. Runaways #6
  45. X-Men: Phoenix #1
  46. All-New Official Handbook of the Marvel Universe A to Z #2; Blaquesmith's entry
  47. X-Factor #235