The cave bear, Ursus spelaeus, represents one of the most frequently found paleontological remains from the Pleistocene in Europe. The species has always been confined to Europe and was contemporary with the brown bear, Ursus arctos. Relationships between the cave bear and the two lineages of brown bears defined in Europe, as well as the origins of the two species, remain controversial, mainly due to the wide morphological diversity of the fossil remains, which makes interpretation difficult [1, 2]. Sequence analysis of ancient DNA is a useful tool for resolving such problems because it provides an independent source of data [3]. We previously amplified a short DNA fragment of the mitochondrial DNA control region (mt control region) of a 40,000-year-old Ursus spelaeus sample [4]. In this paper, we describe the DNA analysis of two mtDNA regions, the control region and the cytochrome b gene. Control region sequences were obtained from ten samples of cave bears ranging from 130,000 to 20,000 years BP, and one particularly well-conserved sample gave a complete cyt b sequence. Our data demonstrate that cave bears split largely before the lineages of brown bears around 1.2 million years ago. Given its abundance, its wide distribution in space and time, and its large morphological diversity, the cave bear is a promising model for direct observation of the evolution of sequences throughout time, extinction periods, and the differentiation of populations shaped by climatic fluctuations during the Pleistocene.
One of the greatest mysteries for most of the twentieth century was the fate of the Romanov family, the last Russian monarchy. Following the abdication of Tsar Nicholas II, he and his wife, Alexandra, and their five children were eventually exiled to the city of Yekaterinburg. The family, along with four loyal members of their staff, was held captive by members of the Ural Soviet. According to historical reports, in the early morning hours of July 17, 1918 the entire family along with four loyal members of their staff was executed by a firing squad. After a failed attempt to dispose of the remains in an abandoned mine shaft, the bodies were transported to an open field only a few kilometers from the mine shaft. Nine members of the group were buried in one mass grave while two of the children were buried in a separate grave. With the official discovery of the larger mass grave in 1991, and subsequent DNA testing to confirm the identities of the Tsar, the Tsarina, and three of their daughters – doubt persisted that these remains were in fact those of the Romanov family. In the summer of 2007, a group of amateur archeologists discovered a collection of remains from the second grave approximately 70 meters from the larger grave. We report forensic DNA testing on the remains discovered in 2007 using mitochondrial DNA (mtDNA), autosomal STR, and Y- STR testing. Combined with additional DNA testing of material from the 1991 grave, we have virtually irrefutable evidence that the two individuals recovered from the 2007 grave are the two missing children of the Romanov family: the Tsarevich Alexei and one of his sisters.
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