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This chapter presents the representations of diabetes as a racialized disease with the ideologies of research participation and humanitarian service found within the sampling apparatuses along the border. It is shown that a transnational protogenetic subject is crafted through the biological embodiment of Mexicana/o ethnicity as an admixed biological group. The chapter also explains the admixture–susceptibility matrix, and offers its resonance with contemporary and historical nativist impulses. The diabetes susceptibility haplotype transforms the conventional epidemiological concern for predicting which persons will become ill to predicting who is an ill person. The chapter demonstrates that while the ideology of diabetes science may interpellate Mexicanas/os into state subjects, it does so by naturalizing a particular social order. Locating diabetes within Mexicana/o ethnoracial admixture cleaves both Mexicanness and the illness called diabetes from the social histories that produced the ethnic label and the socially embodied conditions which contribute to the disease.

The preceding chapters provide extensive information on the context, mortuary rituals, skeletal and dental morphology and morphometrics, dental wear, functional anatomy, paleopathology, and paleochemistry of the human remains from the northern Russian site of Sunghir. The three associated skeletons from Graves 1 and 2 provide the overwhelming volume of data and inferences on the Pleistocene people of Sunghir. Yet the other elements help to fill out a few aspects of the sample. It would be possible, if arduous, to summarize here the various aspects of these human remains that are detailed in the preceding chapters. However, many of the aspects relate to the interpretation of a specific anatomical unit or functional complex. As such, they provide insight into the evolution of these complexes through the Late Pleistocene, as well as inferences regarding their configurations at Sunghir and other Early/Mid Upper Paleolithic (E/MUP) sites. To review each one here would be unnecessarily redundant. Of more interest at this point is to try to fit these people into their Mid Upper Paleolithic (MUP) context and to assess degrees to which the Sunghir human remains might contribute to some of the more general issues relating to last interpleniglacial human populations. In this context, there are aspects of population dynamics, for which the Sunghir humans have some bearing. These aspects involve, in particular, issues of consanguinity and population stability. It has been suggested, based on shared unusual anatomical features, that several of the MUP human skeletal samples (particularly those from multiple burials) include closely related individuals. This has been suggested in particular for the samples from Barma Grande (Formicola 1990), Bausu da Ture (Villotte et al. 2011), Dolní Věstonice II (Vlček 1991; but see data in Fu et al. 2013), and Fanciulli (Grotte des Enfants; Vlček 1965), as well as the El Sidrón Neandertal site (Lalueza-Fox et al. 2011). Moreover, it seems likely that most of these contemporaneous groups of individuals were closely related, if one provides an even generous estimate of the human population densities on the European MUP landscape and the need for individuals to find appropriate mates for reproduction (cf. Wobst 1976).

Chapter 2 deals with the manner in which genetic variation is organized in random-mating populations, including such basics as the Hardy–Weinberg principle, multiple alleles and DNA typing, and X-linkage. These are basic, elementary concepts that set the stage for later chapters. It also includes detailed examination of two-locus linkage disequilibrium (LD), measures of LD, and the levels of LD observed in natural populations. The chi-square test for goodness of fit is discussed, together with its interpretation, along with the basics of hypothesis testing including type I error (false positive), type II error (false negative), power, and the need to correct for multiple comparisons. Also discussed are LD due to population admixture and Wahlund’s principle.

Contemporary Transeurasian-speaking populations reside in a wide geographic area encompassing the Eurasian steppe, Northeast China and the Russian Far East, as well as Korean peninsula and the Japanese archipelago. From population genetic studies of contemporary Transeurasian-speakers, it is well known that they are genetically heterogeneous, probably due to historical mixing with non-Transeurasian populations during their migration. Here, we provide an up-to-date overview of the genetic relationship among Transeurasian populations. Specifically, we focus on highlighting i) studies of contemporary populations explicitly taking into account the above stated recent admixture, and ii) paleogenomic studies of ancient genomes to directly recover prehistoric gene pools predating recent admixture events. These studies show an underlying shared genetic substratum among the Transeurasian populations, which is best represented by ancient populations from Northeast China and the Russian Far East, as well as present-day Tungusic-speaking populations.

Here, some prospects for future studies in the field of electron and nuclear spin dynamics are outlined. In contrast to previous chapters where the electron interaction with multitude of nuclei was discussed, in Chapter 8 particular emphasis is put on a situation where hyperfine interaction is so strong that it leads to a qualitative rear rangement of the energy spectrum resulting in coherent excitation transfer between electron and nucleus. The strong coupling between the spin of the charge carrier and of the nucleus is realized; e.g., in the case of deep impurity centers in semiconductors or in isotopically purified systems. We also discuss the effect of the nuclear spin polaron; that is, the ordered state, where the carrier spin orientation results in alignment of spins of the nucleus interacting with the electron or hole. Such problems have been briefly discussed in the literature but, in our opinion, call for in-depth investigation.

This chapter reviews approaches to how populations of sexually reproducing individuals are defined statistically via genetic criteria. It addresses the question of whether there is a meaningful and practical concept of a population in biology, in the context of recent genomic methods. Current approaches are simpler than a full modelling of relations between individuals, as differences between whole populations need not be described. Rather, when individuals reproduce according to standard genealogical processes, wider populations can then be correctly characterized. This statistical approach is, further, robust to incorrect modelling of differences between populations, and can be extended to whole-genome datasets by means of haplotype modelling. Simple examples and applications to data are used to illustrate these points. Despite limitations that arise when true data contain no discrete populations, the population concept remains a helpful tool in describing biodiversity.

Chapter 8, “Molecular deviants: sequence signatures of selection and demography,” dives into the logic and mechanics of some of the most common tests of neutrality to show how and why data can reveal differences from the predictions of the standard neutral model. It introduces approaches based on skewed patterns of polymorphism alone, including Tajima’s D test, and on differentiation or divergence alone, like the Lewontin-Krakauer, Population Branch Statistic (PBS), and K_A / K_S relative-rates tests. Chapter 8 also covers tests of neutrality that integrate information from both within and between species, including the HKA-test and McDonald-Kreitman (MK) test. The logic for other tests of neutrality also is introduced, including ABBA-BABA, Composite Likelihood Ratio (CLR), Extended Haplotype Homozygosity (EHH), and other approaches. Practical implications of ancestral polymorphism and slightly deleterious polymorphisms are discussed, for example, in calculating and interpreting the neutrality index and fraction of positively selected sites (α‎). The goal of this chapter is to explain the logic of methods applied to molecular population genetic data to read the story of evolutionary history from the genome.

This chapter probes genetic ancestry tests, which are being used increasingly by individuals for a number of reasons. Many are seeking ways to fill in gaps in their family tree; some are hoping to assert membership in certain groups or tribes; and others are simply curious. Nearly 500 test-takers filled out an online survey with questions attempting to form a basis of understanding about the types of people who take these tests, why they take them, and the impact the results have on their identity. There are multiple types of tests offered through various companies, including Y-chromosome tests to infer paternal haplogroup; mitochondrial DNA tests to infer maternal haplogroup; and autosomal or admixture tests, which examine nonsex chromosomes inherited from both parents. The majority of respondents claimed that the tests had an impact on some aspect of their life.