A single change. A course of evolution. A lifetime effect.
Humans are creature of change and among the living, they have the best abilities to adapt. And when the natural world called for the next stage of evolution, individuals with special variations, those who possess unique genomes, were preserved, thereby giving rise to a new species through natural selection.
To put it simply: people who could adapt quickly to their new environment are the ones who deserve to survive and jump up the hierarchy.
For centuries, these new species of humans, albeit shrouded in mystery and secrecy, had been the overlords of the world and the humdrums. Perfectly blending in with the normal humans, they have saved and destroyed civilizations and lives.
By the end of the 20th century, these unique speciation of humans were known within their own race as Erityians—a name befitting of their origins and capabilities--the children of the special blood.