Using contemporary people as proxies for ancient communities is a contentious but necessary practice in anthropology. In southern Africa, the distinction between the Cape KhoeSan and eastern KhoeSan remains unclear, as ethnicity labels have been changed through time and most communities were decimated if not extirpated. The eastern KhoeSan may have had genetic distinctions from neighboring communities who speak Bantu languages and KhoeSan further away; alternatively, the identity may not have been tied to any notion of biology, instead denoting communities with a nomadic "lifeway" distinct from African agro-pastoralism.
View Article and Find Full Text PDFForensic Sci Int Genet
September 2020
We developed a new mutationally well-balanced 32 Y-STR multiplex (CombYplex) together with a machine learning (ML) program PredYMaLe to assess the impact of STR mutability on haplogourp prediction, while respecting forensic community criteria (high DC/HD). We designed CombYplex around two sub-panels M1 and M2 characterized by average and high-mutation STR panels. Using these two sub-panels, we tested how our program PredYmale reacts to mutability when considering basal branches and, moving down, terminal branches.
View Article and Find Full Text PDFForensic genetic laboratories perform a large amount of STR analyses of the Y chromosome, in particular to analyze the male part of complex DNA mixtures. However, the statistical interpretation of evidence retrieved from Y-STR haplotypes is challenging. Due to the uni-parental inheritance mode, Y-STR loci are connected to each other and thus haplotypes show patterns of relationship on the familial and population level.
View Article and Find Full Text PDFForensic Science International: Genetics and Forensic Science International: Reports communicate research on a variety of biological materials using genetics and genomic methods. Numerous guidelines have been produced to secure standardization and quality of results of scientific investigations. Yet, no specific guidelines have been produced for the ethical acquisition of such data.
View Article and Find Full Text PDFIn forensic casework, Y-chromosome short tandem repeats (Y-STRs) are essential for differentiating between unrelated males and resolving the male component of admixed biological evidence. While the majority of Y-STRs are adequate for discriminating between different paternal lineages, rapidly mutating Y-STRs are necessary for improving discrimination between males within populations of low Y-chromosome diversity and between paternal relatives. Alternatively, sequencing of Y-STRs may also improve the discrimination between isometric Y-STR alleles by identifying variation in the repeat unit pattern arrangements and by identifying SNPs in the flanking region or within the STR repeat unit itself.
View Article and Find Full Text PDFPopulation structure was investigated in 990 Botswana individuals according to ethno-linguistics, Bantu and Khoisan, and geography (the nine administrative districts) using the Identifiler autosomal microsatellite markers. Genetic diversity and forensic parameters were calculated for the overall population, and according to ethno-linguistics and geography. The overall combined power of exclusion (CPE) was 0.
View Article and Find Full Text PDFWe report the findings of the evaluation of the InnoTyper 21 genotyping kit for the use of human identification (HID) and paternity testing in South Africa. This novel forensic kit evaluates 20 retrotransposable elements (AC4027, MLS26, ALU79712, NBC216, NBC106, RG148, NBC13, AC2265, MLS09, AC1141, TARBP, AC2305, HS4.69, NBC51, ACA1766, NBC120, NBC10, NBC102, SB19.
View Article and Find Full Text PDFCE equipment detects and deconvolutes mixtures containing up to six fluorescently labeled DNA fragments. This deconvolution is done by the collection software that requires a spectral calibration file. The calibration file is used to adjust for the overlap that occurs between the emission spectra of fluorescence dyes.
View Article and Find Full Text PDFForensic Sci Int Genet
September 2016
In this study, the GlobalFiler(®) Express amplification kit was evaluated for forensic use in 541 South African individuals belonging to the Afrikaaner, amaXhosa,(1) amaZulu,(1) Asian Indian and Coloured population groups. Allelic frequencies, genetic diversity parameters and forensic informative metrics were calculated for each population. A total of 301 alleles were observed ranging between 5 and 44.
View Article and Find Full Text PDFThe utilization of binary markers in human individual identification is gaining ground in forensic genetics. We analyzed the polymorphisms from the first commercial indel kit Investigator DIPplex (Qiagen) in 512 individuals from Afrikaner, Indian, admixed Cape Colored, and the native Bantu Xhosa and Zulu origin in South Africa and evaluated forensic and population genetics parameters for their forensic application in South Africa. The levels of genetic diversity in population and forensic parameters in South Africa are similar to other published data, with lower diversity values for the native Bantu.
View Article and Find Full Text PDFSeventeen Y-chromosomal short tandem repeats (YSTRs)-DYS19, DYS389I, DYS389II, DYS385a/b, DYS390, DYS391, DYS392, DYS393, DYS437, DYS438, DYS439, DYS448, DYS456, DYS458, DYS635, and Y-GATA-H4-were analyzed in 252 unrelated male individuals from Botswana. A total of 238 unique haplotypes were identified. The discrimination capacity (DC) was 0.
View Article and Find Full Text PDFA consensus on Bantu-speaking populations being genetically similar has emerged in the last few years, but the demographic scenarios associated with their dispersal are still a matter of debate. The frontier model proposed by archeologists postulates different degrees of interaction among incoming agropastoralist and resident foraging groups in the presence of "static" and "moving" frontiers. By combining mitochondrial DNA and Y chromosome data collected from several southern African populations, we show that Bantu-speaking populations from regions characterized by a moving frontier developing after a long-term static frontier have larger hunter-gatherer contributions than groups from areas where a static frontier was not followed by further spatial expansion.
View Article and Find Full Text PDFBackground: Wild animals' meat is extensively consumed in South Africa, being obtained either from ranching, farming or hunting. To test the authenticity of the commercial labels of meat products in the local market, we obtained DNA sequence information from 146 samples (14 beef and 132 game labels) for barcoding cytochrome c oxidase subunit I and partial cytochrome b and mitochondrial fragments. The reliability of species assignments were evaluated using BLAST searches in GenBank, maximum likelihood phylogenetic analysis and the character-based method implemented in BLOG.
View Article and Find Full Text PDFThe study of Y chromosome variation has helped reconstruct demographic events associated with the spread of languages, agriculture, and pastoralism in sub-Saharan Africa, but little attention has been given to the early history of the continent. In order to overcome this lack of knowledge, we carried out a phylogeographic analysis of haplogroups A and B in a broad data set of sub-Saharan populations. These two lineages are particularly suitable for this objective because they are the two most deeply rooted branches of the Y chromosome genealogy.
View Article and Find Full Text PDFDuring the study of genetic diversity at non-core Y-STRs in South African population groups, we identified loci with high discrimination capacity. In this study we present a detailed account of the allele diversity, allele sequence data, gene diversity, allele frequency spectrum and informativeness for assignment in the European English, Asian Indian and Xhosa population groups at loci DYS449, DYS481, DYS518, DYS612, DYS626, DYS644 and DYS710. The suitability of these loci for forensic, genealogical and evolutionary studies is discussed, and nomenclature for loci DYS518, DYS612, DYS626 and DYS644 is suggested.
View Article and Find Full Text PDFTwo Y-STR genotyping systems were evaluated for usefulness in forensic casework in the Cape Muslim population of South Africa. Samples were collected from 105 males, and genotyped for 17 loci amplified in two multiplexes. Allele and haplotype frequencies were determined for nine Y-STR loci used to define the minimal haplotype (DYS19, DYS389-I, DYS389-II, DYS390, DYS391, DYS392, DYS393, and the duplicated locus DYS385) amplified in one multiplex, as well as for eight widely used loci amplified in a second multiplex and consisting of DYS449, DYS481, DYS518, DYS557, DYS570, DYS607, DYS612 and DYS614.
View Article and Find Full Text PDFThe impact of geographic heterogeneity and historical demographic factors on genetic diversity in the commercially exploited hake Macruronus magellanicus was examined applying microsatellite markers. A total of 450 fish from 6 different sites, collected in Atlantic Patagonia, were genotyped at 6 polymorphic loci. While analysis of variance-based methods (Fst-Rst) failed to detect differentiation, the exact test for genic differentiation and factorial correspondence analysis revealed subtle differences between coastal and continental shelf edge samples.
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