A result of the Bene Gesserit breeding program, Jessica was the illegitimate daughter of Baron Vladimir Harkonnen and an unknown mother. The Bene Gesserit breeding charts note that Jessica's birth mother was named Tanidia Nerus. She was raised from birth by the Bene Gesserit, who intended to breed her to the House Atreides heir Leto I, to produce a daughter who would then breed with Feyd Rautha Harkonnen in order to produce the Kwisatz Hadarach, the one who would not only possess the genetic memories of all male and female ancestors, but also see into the future.