There's one thing I noticed while reading Jack the Bodiless that may or may not be a plothole. Maybe someone can clarify if I'm mistaken about one thing:
Theresa Kendall is the granddaughter of Elaine Donovan and Don Remillard. So wouldn't this mean she has the immortal Remillard genes as well? She did die unnaturally at a relatively young age, so perhaps it was never apparent, but if you look at Elaine and Donny's daughter -- Theresa's mother -- you see she did die at a ripe old age. In Jack the Bodiless, there's even a reference that Annarita Latimer refused regen tank therapy and died elderly in 2056.
With the exception of Jack, there is no recorded Remillard born after Rogi and Don that did not have the immortality gene. Even though Theresa and her mother Annarita were not Remillards by name, they were by blood.
As meticulous as Julain May is to detail, I'd be a bit surprised if such a big flub went by her unnoticed. Are there any theories or explanations about the genetics behind these two characters?