All lifeforms have the Lineage Factor, and by manipulating it from a young age, the growth of a lifeform can be changed. Eating a Devil Fruit affects one's Lineage Factor, which allows them to gain a supernatural power.
Artificial Devil Fruits
- Further information: Artificial Devil Fruit
By extracting Kaidou's Lineage Factor, Dr. Vegapunk was able to replicate the Emperor's Uo Uo no Mi, Model: Seiryu at some point in the past. Despite interest from the World Government in the replica, however, Vegapunk deemed the experiment a "failure" for unknown reasons, leaving it behind in the Third Research Institute after Caesar Clown caused an island-wide explosion on Punk Hazard. Because of this, the World Government believed the replica was lost among the destruction.
The replicated fruit, however, was left intact, being eventually found and eaten by a starving Momonosuke. In spite having little control over its effects, Momonosuke is still able to transform into a full dragon and summon flame clouds for flight, meaning that despite being a "failed" experiment, the fruit works very closely to the way an actual Zoan Devil Fruit functions.
- Further information: SAD
By applying Lineage Factor, Caesar Clown was able to create SAD, a key ingredient used in the development of Artificial Devil Fruits known as SMILES, as explained by Trafalgar Law. However, they are restricted to the Zoan-class.
- Further information: Modified Humans
While his wife was pregnant, Judge forced her to undergo the surgery which manipulated the Lineage Factor of the four fetuses she was carrying. However, due to Sora's interference, only three of their four sons were born as modified humans. After their birth, they were further experimented on, including being administered drugs, in order to increase their development. These experiments were also performed on their elder sister.
The successfully modified sons (Ichiji, Niji and Yonji) developed an Exoskeleton (外骨格 Gaikokkaku?), gained an increased healing ability, and, with training, rapidly increased in strength and resilience; soon, these qualities developed to a point equaling those of adult soldiers, while the children were in their early childhood. Supposedly, the modifications also took away their ability to feel emotions. However, Ichiji, Niji, and Yonji are able to be attracted to pretty women, laugh at jokes, and ridicule Sanji.
While Reiju received the same physical enhancements, she retained her emotions, but lost the ability to refuse Judge's orders.
- Further information: Cloning
Vinsmoke Judge conducted several researches and experiments with the Lineage Factor, becoming able to artificially manufacture human beings to fill the soldier ranks of Germa 66. Those soldiers are known as Clone Soldiers (
- The Lineage Factor is a reference to DNA, the molecule that contains all the genetic information of the host organism.
- Despite the fact that a Devil Fruit changes one's Lineage Factor, the effects do not appear to be hereditary. Charlotte Linlin, who gained the Soru Soru no Mi powers at the age of six, had 85 children, who did not inherit her ability in any way and were able to eat their own Devil Fruits.
- One Piece Manga and Anime — Vol. 84 Chapter 840 (p. 3-5) and Episode 802, Yonji explains the Lineage Factor and cloning.
- One Piece Manga and Anime — Vol. 70 Chapter 698 (p. 17) and Episode 625, Law explains that Caesar's research is an application of Vegapunk's genetics research.
- One Piece Manga and Anime — Vol. 85 Chapter 852 (p. 10-13, 16-17) and Episodes 819–820, Reiju tells Sanji about their mother's intention.
- One Piece Manga and Anime — Vol. 84 Chapter 840 (p. 10-16) and Episode 803, The Vinsmoke children's training is shown.