Individual DNA identification from ancient human remains.

Individual identification of ancient human remains is one of the most fundamental requisites for studies of paleo-population genetics, including kinship among ancient people, intra- and interpopulation structures in ancient times, and the origin of human populations. However, knowledge of these subjects has been based mainly on circumstantial archaeological evidence for kinship and intrapopulation structure and on genetic studies of modern human populations. Here we describe individual identification of ancient humans by using short-nucleotide tandem repeats and mtDNAs as genetic markers. The application of this approach to kinship analysis shows clearly the presence or absence of kinship among the ancient remains examined.     

Biological and environmental agents in the preservation of ancient human remains.

In osteological studies, the state of preservation of the material assumes great importance in the case of histopathological, histomorphological and histomorphometric analyses of thin sections. The aims of the present study were to compare osteological samples from graves of different eras and geographical sites in order to identify possible similarities or differences in the quantitative and qualitative action of fungal and bacterial contaminants and to throw light on the importance of the diagenetic processes that the bone undergoes from the moment of its deposition in the ground to its conservation in laboratories and museums. Analysis by polarized light microscopy revealed large qualitative and quantitative differences between the samples and great variability in the modalities of infestation. The present study demonstrates that post-mortem alterations due to the action of biological agents can in some cases invalidate the analysis of osteological samples, by rendering the material unsuitable for observation and diagnosis.     

Estimating the distribution of probable age-at-death from dental remains of immature human fossils

In two historic longitudinal growth studies, Moorrees et al. (Am J Phys Anthropol 21 (1963) 99-108; J Dent Res 42 (1963) 1490-1502) presented the "mean attainment age" for stages of tooth development for 10 permanent tooth types and three deciduous tooth types. These findings were presented graphically to assess the rate of tooth formation in living children and to age immature skeletal remains. Despite being widely cited, these graphical data are difficult to implement because there are no accompanying numerical values for the parameters underlying the growth data. This analysis generates numerical parameters from the data reported by Moorrees et al. by digitizing 358 points from these tooth formation graphs using DataThief III, version 1.5. Following the original methods, the digitized points for each age transition were conception-corrected and converted to the logarithmic scale to determine a median attainment age for each dental formation stage. These values are subsequently used to estimate age-at-death distributions for immature individuals using a single tooth or multiple teeth, including estimates for 41 immature early modern humans and 25 immature Neandertals. Within-tooth variance is calculated for each age estimate based on a single tooth, and a between-tooth component of variance is calculated for age estimates based on two or more teeth to account for the increase in precision that comes from using additional teeth. Finally, we calculate the relative probability of observing a particular dental formation sequence given known-age reference information and demonstrate its value in estimating age for immature fossil specimens.     

Genetic identification of missing persons: DNA analysis of human remains and compromised samples

Human identification has made great strides over the past 2 decades due to the advent of DNA typing. Forensic DNA typing provides genetic data from a variety of materials and individuals, and is applied to many important issues that confront society. Part of the success of DNA typing is the generation of DNA databases to help identify missing persons and to develop investigative leads to assist law enforcement. DNA databases house DNA profiles from convicted felons (and in some jurisdictions arrestees), forensic evidence, human remains, and direct and family reference samples of missing persons. These databases are essential tools, which are becoming quite large (for example the US Database contains 10 million profiles). The scientific, governmental and private communities continue to work together to standardize genetic markers for more effective worldwide data sharing, to develop and validate robust DNA typing kits that contain the reagents necessary to type core identity genetic markers, to develop technologies that facilitate a number of analytical processes and to develop policies to make human identity testing more effective. Indeed, DNA typing is integral to resolving a number of serious criminal and civil concerns, such as solving missing person cases and identifying victims of mass disasters and children who may have been victims of human trafficking, and provides information for historical studies. As more refined capabilities are still required, novel approaches are being sought, such as genetic testing by next-generation sequencing, mass spectrometry, chip arrays and pyrosequencing. Single nucleotide polymorphisms offer the potential to analyze severely compromised biological samples, to determine the facial phenotype of decomposed human remains and to predict the bioancestry of individuals, a new focus in analyzing this type of markers.     

Biomolecular identification of ancient Mycobacterium tuberculosis complex DNA in human remains from Britain and continental Europe

Tuberculosis is known to have afflicted humans throughout history and re‐emerged towards the end of the 20th century, to an extent that it was declared a global emergency in 1993. The aim of this study was to apply a rigorous analytical regime to the detection of Mycobacterium tuberculosis complex (MTBC) DNA in 77 bone and tooth samples from 70 individuals from Britain and continental Europe, spanning the 1st–19th centuries AD. We performed the work in dedicated ancient DNA facilities designed to prevent all types of modern contamination, we checked the authenticity of all products obtained by the polymerase chain reaction, and we based our conclusions on up to four replicate experiments for each sample, some carried out in an independent laboratory. We identified 12 samples that, according to our strict criteria, gave definite evidence for the presence of MTBC DNA, and another 22 that we classified as “probable” or “possible.” None of the definite samples came from vertebrae displaying lesions associated with TB. Instead, eight were from ribs displaying visceral new bone formation, one was a tooth from a skeleton with rib lesions, one was taken from a skeleton with endocranial lesions, one from an individual with lesions to the sacrum and sacroiliac joint and the last was from an individual with no lesions indicative of TB or possible TB. Our results add to information on the past temporal and geographical distribution of TB and affirm the suitability of ribs for studying ancient TB. Am J Phys Anthropol 153:178–189, 2014. © 2013 Wiley Periodicals, Inc.     

Retrieving chronological age from dental remains of early fossil hominins to reconstruct human growth in the past

A chronology of dental development in Pan troglodytes is arguably the best available model with which to compare and contrast reconstructed dental chronologies of the earliest fossil hominins. Establishing a time scale for growth is a requirement for being able to make further comparative observations about timing and rate during both dento-skeletal growth and brain growth. The absolute timing of anterior tooth crown and root formation appears not to reflect the period of somatic growth. In contrast, the molar dentition best reflects changes to the total growth period. Earlier initiation of molar mineralization, shorter crown formation times, less root length formed at gingival emergence into functional occlusion are cumulatively expressed as earlier ages at molar eruption. Things that are similar in modern humans and Pan, such as the total length of time taken to form individual teeth, raise expectations that these would also have been the same in fossil hominins. The best evidence there is from the youngest fossil hominin specimens suggests a close resemblance to the model for Pan but also hints that Gorilla may be a better developmental model for some. A mosaic of great ape-like features currently best describes the timing of early hominin dental development.     

Approaches to the identification of angiosperm leaf remains

During the past 125 years the history of early angiosperms, interpreted through the fossil leaf record has been largely an exercise in paleofloristic studies, ignoring evolution. Imprecise identifications of ancient leaves “matched” to extant genera and families have been used as the basis for reconstructions of paleocommunities and paleoclimates. However, as the result of careful morphological studies of leaf form, venation and cuticular features new insights into the evolution of angiosperms are now available. In this paper considerations are given to the usefulness and shortcomings of leaf form, venation and cuticular analysis as diagnostic tools of plant identification. Many techniques for the study of the morphology of modern and fossil leaves are included in this paper as well as tables outlining features of leaf venation and the epidermis. Careful morphological studies of leaf form (such as the venation and epidermal characters emphasized in this paper) will provide better understanding of the relationships of living angiosperms and transform the fossil leaf record into useful data that can be used to study the evolution of the angiosperms.     

Chemical and physical methods in dating human skeletal remains

Chemical and physical methods for dating skeletal remains were examined. Benzidine reaction, ultra-violet fluorescence, specific gravity and supersonic conductivity were carried out on 71 dated skeletal findings distributed over the span of the last 3,500 years. Results given by benzidine reaction and ultra-violet fluorescence basically coincide, and positive readings were obtained up to about 200–350 years. Values measured in specific gravity and supersonic conductivity testing show a parallel trend, pointing out a clear difference between samples of the three first centuries and the ones belonging to more ancient periods examined.     

A new approach for calibrating dental caries frequency of skeletal remains

It is a fact that researchers make use of various calibration methods for calculating and correcting dental caries frequency. The lack of standardization and accuracy of such methods has made it difficult for the researchers to draw reliable and differentiated conclusions from caries frequencies. Besides, the number of studies on how far the calculation methods reflect the "real" caries frequency is very limited. In this study, various methods for calculating caries frequency in skeletal samples are discussed and a new calculation method is proposed for estimating "real" caries frequency. The Hardwick's correction, which is one of the methods discussed in this study, is not successful in estimating "real" caries frequency as it proposes standard values for different life styles and dietary habits. The decayed and missing index is also considered inefficient as it assumes that all antemortem tooth loss is due to caries. The caries correction factor, proposed by Lukacs, achieves more successful results by considering factors other than caries in antemortem tooth loss, but because it does not differentiate between the anterior and posterior tooth groups during calculation, the results to be obtained therefrom may deviate from actual figures. In order to correct any such deviation, the caries correction factor must be applied separately for the anterior and posterior teeth groups since the resistance of each group to cariogenic factors is different. All the methods outlined above do not consider the effects of postmortem tooth loss on caries frequency. As a result, these methods are still far from reflecting a reliable caries frequency. The application of a proportional correction factor--as a technique newly introduced here--corrects the deviation caused by postmortem tooth loss and achieves more realistic results.     

ABO blood typing of human skeletal remains in Hungary

The author reports about the theoretical effects of his paleoserologic investigations on some historical population genetics problems. First he refers to the essence of the two modifications by the help of which the fluorescent antibody method can be made suitable for blood typing or archeological skeletal remains and determines his working units (sample, series, "population") used in the paleoserologic researches. The benefits of the projection of the ABO blood typing results on the map of the cemetaries are demonstrated. The distribution of the several phenotypes are collated to the character or richness of the grave goods and to the taxonomic features of the late individuals. The thorough examination of the serogenetic distances among the several samples of a given historical period may cast more light on the ethnic interrelations of the earlier populations living in the same geographic area. Following up the serogenetic changes of a population during subsequent historical periods, new ideas can be gained about the importance of the environmental, economic, and demographic factors shaping the serogenetic profile of the population.