Bene Gesserit Reverend Mothers (those who survive the water of life) gain access to the genetic memory of their entire female lineage. The Kwisatz Haderach is special because he can see BOTH the female and male genetic memory of his lineage, AND see infinitely into the future. That's how he knew about the Baron being Jessica's father. Spacing Guild Navigators are men who underwent a spice transformation and can see a limited version of the future, but cannot see genetic lineage. The Navigators can navigate hyperspace because of their ability see see briefly into the future, it allows them to see what the safest path through hyperspace is because they can see which paths would destroy them and which wouldn't.
The reason Alia was called Abomination upon her birth is because Jessica was pregnant with her when she underwent the water of life transformation. This meant that Alia also became a Reverend Mother, but she did so before she developed a strong personality of her own. Having the memories of her entire genetic lineage arise before she developed her own character meant that she would have no sense of self, resulting in her adopting characteristics of her many ancestors instead.
You're supposed to get all of this out of Book 1 (Dune), but it's easy to miss on your first reading.
The reason Alia was called Abomination upon her birth is because Jessica was pregnant with her when she underwent the water of life transformation. This meant that Alia also became a Reverend Mother, but she did so before she developed a strong personality of her own. Having the memories of her entire genetic lineage arise before she developed her own character meant that she would have no sense of self, resulting in her adopting characteristics of her many ancestors instead.
You're supposed to get all of this out of Book 1 (Dune), but it's easy to miss on your first reading.