Update.
Knight, Zhivotovsky et al tested the finger of Alexandra's sister Elizabeth, and found that it doesn't match the published findings.
They also found that the Elizabeth finger was contaminated with DNA from 2 other individuals, while the Gill test of 9 individuals buried in loamy soil for 75 years and handled (seemingly) by everybody from the Minister of Internal Affairs to Bob Atchison, showed no contamination whatsoever is a bit of a stretch, don't you think?
Just teasing Bob, I'm sure you didn't touch the remains because if you had done so, some of your DNA may have contaminated them. And of course, they were never handled in any way other than with the most proper scientific forensic rigour for the 8 odd years they were sitting there in the open on a steel slab in Ekaterinburg, right? :-/