Analysis of Russian Royals and DNA
The difficulty for DNA analysis of these bones was that they had been buried in Siberia. The ground is frozen for 10 months of the year and then water is present; conditions that are not ideal for the preservation of DNA. Eventually DNA was extracted and sent to several labs around the world. By comparing mitochondrial DNA of the skeletons to each other and to living members of the Romanov family, scientists were able to conclude that;
1) There was a match between the Tsarina, the three children and a living maternal relative.
2) The DNA from the Tsar's skeleton matched the DNA from two living maternal relatives.
3) The other four skeletons were unrelated.
The scientists also looked at DNA segments called STR's - short tandem repeats. Five of the skeletons had similar STR sequences and patterns of distribution. This showed that they were related.
However, this analysis of the Russian royals and their DNA left two mysteries needing to be solved. Firstly, the skeletons of the Tsar and Tsarina's two other children were missing, including that of Tsarevich, Alexei. Secondly, a woman known as Anna Anderson had for years been claiming to be Anastasia, the youngest daughter of the Tsar and his wife. She'd even managed to convince some members of the Romanovs, but was she really who she said she was? Now DNA analysis would soon be able to clear up the matter.
She had died in 1984 and her body had been cremated so DNA analysis was not an option here. But a journalist managed to find the hospital where Anderson had had her appendix removed. In the medical records was a slide containing a tissue sample. This sample was analysed and found not be a match to any Romanovs. So that was one mystery solved.
The second mystery was solved in 2008 when bone fragments found near the burial pit in Yekaterinburg underwent DNA analysis. The testing confirmed that the remains belonged to Alexei and his sister Princess Maria.