Character mistake: When Olivia and Dr Galina are in the bathroom, Galina mentions an umbilical chord, from a baby whose mother died (Nadia), that contained Olivia's mitochondrial DNA. Mitochondrial DNA comes from the mother, so Nadia's Mitochondrial DNA came from Letha who got hers from Marie, absolutely nothing to do with Olivia.
Factual error: The show is supposed to be set in Pennsylvania. But when Roman is getting treatment in a doctor's office, and his phone vibrates on a table next to him, a close up shot of his phone is shown and the cell service is ROGERS. This cell service is only in Canada.