Point taken: An unusual case of incisor agenesis and mandibular trauma in Early Bronze Age Siberia.

This paper focuses on the mandible of an adult male individual (radiocarbon dated to 4420-3995cal BP) from the Early Bronze Age Cis-Baikal cemetery of Ust'-Ida I (Siberia, Russian Federation). The mandible contains two features of interest: (1) bilaterally missing central incisors, and (2) the tip of a lithic projectile point embedded in the symphyseal region. Despite the absent teeth, the mandible presents a dental arcade without diastemata, appearing normal and complete on first glance. Three different levels of CT (computed tomography) imaging-ranging from clinical to synchrotron-based-were employed in order to establish the aetiology behind the missing dentition, whether subsequent to the projectile trauma or entirely unrelated to it. Results indicate that the mandible exhibits two highly unusual but unrelated features: probable bilateral agenesis of the central incisors and perimortem trauma to the mental symphysis. In addition, the embedded tip was successfully matched via digital imaging to photographs of a broken projectile point, an artefact recovered from the facial region of the skeleton.

[Molecular genetic characteristics of the neolithic population of the Baikal region: RFLP analysis of the ancient mitochondrial DNA from osseous remains found in the Ust-Ida I burial ground]. / Molekuliarno-geneticheskaia kharakteristika neoliticheskoi populiatsii Pribaikal'ia. Analiz PDRF drevnei mtDNK iz ostankov v Mogil'nike ust'-Ida I.

Nineteen mtDNA samples from osseous remains found in the Ust-Ida I burial ground (middle Angara River) were analyzed. An ancient population dated back to 4020-3210 B.C. by radiocarbon (14C) analysis and archeologically assigned to the Neolithic Isakovo culture of the Baikal region was described in terms of molecular genetics. Data on restriction-site polymorphisms in fragment 16,106-16,545 of the mtDNA D-loop were obtained for seven restriction endonucleases. On the basis of these data, the mitotypic structure and nucleotide diversity of the ancient population were determined. The molecular genetic characteristics of the Neolithic population were compared to the modern populations of Siberia, Mongolia, and Urals. The data obtained indicate that the studied Baikal Neolithic population was ancestral for the modern indigenous Siberian population. The time of divergence of the three regional populations (5572 years ago) was estimated from the genetic distances between the Neolithic and modern Siberian populations, assuming that the average rate of nucleotide substitution was constant. This estimation agrees with the results of the radiocarbon dating (5542-5652 years ago). The fact that the studied samples were 14C-dated allowed the rate of nucleotide substitution in the studied region of mtDNA D-loop to be directly determined.