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Attempts were made to detect ancient DNA (aDNA) in samples of 88 human skeletons from eight Neolithic and Bronze Age sites in Greece and Crete. Ancient DNA was absent in specimens from Nea Nikomedia, Lerna, Karaviádena (Zakro), Antron Grave Circle A and Mycenae Grave Circle A. For each of three skeletons from Antron Grave Circle B that were sampled, polymerase chain reactions (PCRs) gave products for nuclear but not mitochondrial DNA, but amplicon yield was low and inconsistent with replicate PCRs failing to give reproducible results. With specimens from Mycenae Grave Circle B, evidence for mitochondrial aDNA was obtained for four of the 22 skeletons that were studied, and at Kouphovouno evidence for mitochondrial and/or nuclear aDNA was obtained with eight of the 20 skeletons that were examined. We conclude that, although aDNA might be present in some Eastern Mediterranean skeletons from later centuries of the Bronze Age, it is not commonly found in material from this period and is likely to be absent from older material.  相似文献   
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The domestic dog fulfills many functions for their human companions, such as hauling, guarding, and protection. Consequently, humans have taken dogs to nearly every corner of the globe. Recent translocations of Western dogs stemming from the Victorian era dog fancy have erased some of the ancient genetic signatures of these earlier migrations. Here we used DNA of ancient and modern dogs from the North American Arctic of Alaska and Greenland to assess their genetic continuity in time and space. We successfully sequenced 23 archaeological (ca. AD 1250–1910) and recent (ca. AD 1930–1990) surface-collected Canis bone and tooth samples and compared them to 51 modern Inuit Sled Dogs and to published sequences of modern Alaskan Malamutes (and additional Inuit Sled Dogs) to test for evidence of lineage replacement or genetic continuity through time. Ancient samples from Alaska and Greenland and modern sequences from Greenland all contained a high frequency of haplotype A31, which was previously described only in modern North American Arctic dogs. Thus, A31 was a common thread tying the entire North American Arctic together prior to European colonization and, in the Eastern Arctic, indicates genetic continuity between past and present dogs as well. However, A31 is rare in modern Alaskan dogs, consistent with post-colonization replacement by Eurasian matrilines.  相似文献   
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