 His daughter Marina Botkina Schweitzer's DNA was later used to help identify the remains of her grandfather, Yevgeny Botkin, after they were exhumed along with other Romanovs in 1991 from a mass grave discovered in Ganina Yama near Yekaterinburg.Schweitzer's DNA was compared against the DNA of her maternal half-sister Kira, who also gave a blood sample, to help scientists isolate the DNA Schweitzer shared in common with her grandfather.This enabled scientists to create a "Botkin DNA profile" and use it to positively identify Dr. Botkin.