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Autochthonous Population (autochthonous + population)
Selected AbstractsNear Eastern Neolithic genetic input in a small oasis of the Egyptian Western DesertAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 2 2009Martina Kujanová Abstract The Egyptian Western Desert lies on an important geographic intersection between Africa and Asia. Genetic diversity of this region has been shaped, in part, by climatic changes in the Late Pleistocene and Holocene epochs marked by oscillating humid and arid periods. We present here a whole genome analysis of mitochondrial DNA (mtDNA) and high-resolution molecular analysis of nonrecombining Y-chromosomal (NRY) gene pools of a demographically small but autochthonous population from the Egyptian Western Desert oasis el-Hayez. Notwithstanding signs of expected genetic drift, we still found clear genetic evidence of a strong Near Eastern input that can be dated into the Neolithic. This is revealed by high frequencies and high internal variability of several mtDNA lineages from haplogroup T. The whole genome sequencing strategy and molecular dating allowed us to detect the accumulation of local mtDNA diversity to 5,138 ± 3,633 YBP. Similarly, theY-chromosome gene pool reveals high frequencies of the Near Eastern J1 and the North African E1b1b1b lineages, both generally known to have expanded within North Africa during the Neolithic. These results provide another piece of evidence of the relatively young population history of North Africa. Am J Phys Anthropol, 2009. © 2009 Wiley-Liss, Inc. [source] Sperm Cryopreservation in Brown Bear (Ursus arctos): Preliminary AspectsREPRODUCTION IN DOMESTIC ANIMALS, Issue 2008L Anel Contents The development of sperm cryopreservation procedures in brown bear is the basis for establishing a specific genetic resource bank aimed at the preservation of a Cantabric brown bear population, which is seriously threatened. Several issues complicate the development of these cryopreservation procedures: lack of previous specific studies, a high incidence of urospermia and spermagglutination observed in bear ejaculates. Moreover, the availability of individuals for research from these threatened populations is problematic. In the case of the Cantabric brown bear, we have used males from other populations, but of the same species, as surrogates, to carry out a direct extrapolation of the results. Urospermia , Moreover, 70% of the ejaculates are urine contaminated and spermagglutination have a detrimental effect on post-thawing cell quality recovery in this species. Considering the high value of these samples (autochthonous population with few individuals), a pre-selection of the ejaculates is not a viable alternative. Preventive methods reducing the mentioned detrimental effects need to be developed. On the basis of previous data, we can suppose that bear spermatozoa resist freezing injuries well. Nevertheless, because of the scarcity of this information, it is necessary to conduct further research on bear semen freezing under field conditions. Epidydimal spermatozoa can be important for genetic resource banking of threatened populations and thus specific cryobiological protocols need to be assayed. To date, 168 brown bear ejaculates have been frozen by the ITRA-ULE group at the University of León (Spain) in the development of methodologies for the preservation of brown bear sperm. [source] Phylogeography of the last surviving populations of Rhodian and Anatolian fallow deer (Dama dama dama L., 1758)BIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 4 2008MARCO MASSETI The European fallow deer (Dama dama dama) is one of the most widespread cervids, and its distribution has been heavily affected by man. At present, only one wild autochthonous population is reputed to survive in Anatolia, but its census size is dramatically decreasing. This means that a significant portion of the ancestral genetic diversity of this taxon is seriously threatened. In the present study, a portion of the mitochondrial DNA (D-loop) in 37 D. d. dama specimens from three Mediterranean sites, Turkey, the island of Rhodes (Greece), and the Italian Peninsula, and seven individuals of the Persian fallow deer, Dama dama mesopotamica, was sequenced, and the results from the data analysis are interpreted in light of current archaeozoological and biogeographical knowledge. We conclude that: (1) D. d. mesopotamica is strongly differentiated from D. d. dama, confirming the results of previous genetic studies and (2) the Rhodian populations of D. d. dama, founded by humans in Neolithic times, possess a set of mitochondrial lineages, found in no other study populations. The persistence of these haplotypes is particularly significant because human-mediated processes (e.g. domestication) usually result in genetic depletion and erosion of an ancestral genetic pool. In the case of the Rhodes' population of fallow deer, we hypothesize that, during the foundation of this population, humans unknowingly preserved a remarkable portion of the original genetic diversity of the source population(s). © 2008 The Linnean Society of London, Biological Journal of the Linnean Society, 2008, 93, 835,844. [source] Microsatellite variation in autochthonous and introduced populations of the Alpine marmot (Marmota marmota) along a European west,east transectJOURNAL OF ZOOLOGICAL SYSTEMATICS AND EVOLUTIONARY RESEARCH, Issue 1 2004L. Kruckenhauser Abstract Microsatellite variation was studied in 11 populations of the Alpine marmot along a west,east transect through the present distribution range. The samples represent five autochthonous and six introduced populations. Eleven loci were analysed in nine populations and six loci in the two populations from France. In the populations from the Western Alps, there is no indication for reduced variability as has been assumed in previous studies. However, a decrease of variation in the autochthonous populations was observed from the west to the east. The introduced populations showed a heterogeneous pattern reflecting the geographic origin of the released individuals. The population from the Spanish Pyrenees harbours a high level of variation and is genetically closest to the French populations. In Austria, three of the introduced populations have low variation and are closely related to the autochthonous populations from the western part of Austria. In contrast, two introduced populations from the central part of Austria are highly variable and resemble the populations from France. At least for one of these populations an early introduction of founder individuals from the Western Alps has been documented. Zusammenfassung Die Mikrosatellitenvariation wurde in 11 Populationen des Alpenmurmeltieres entlang eines west-ost Gradienten durch das gegenwärtige Verbreitungsgebiet untersucht. Die Stichproben repräsentieren fünf autochthone und sechs eingebürgerte Populationen. Elf Loci wurden in neun Populationen analysiert und sechs Loci in den beiden Populationen aus Frankreich. In den Populationen aus den Westalpen ergab sich im Gegensatz zu früheren Untersuchungen kein Hinweis auf eine Reduktion der Variabilität. Innerhalb der autochthonen Populationen ist jedoch eine Abnahme der Variation von Westen nach Osten festzustellen. Die eingebürgerten Populationen zeigten ein uneinheitliches Muster, welches den geografischen Ursprung der ausgesetzten Individuen widerspiegelt. Die Population aus den spanischen Pyrenäen besitzt eine hohe Variation und ist genetisch den französischen Populationen am ähnlichsten. In Österreich zeigen drei der eingebürgerten Populationen niedrige Variation und sind den autochthonen Populationen aus Westösterreich am nächsten verwandt. Hingegen sind die beiden eingebürgerten Populationen aus Zentralösterreich hoch variabel und den Populationen aus Frankreich ähnlich. Zumindest für eine dieser beiden Populationen ist eine frühe Einbürgerung von Gründerindividuen aus den Westalpen dokumentiert. [source] Paleogenetical study of pre-Columbian samples from Pampa Grande (Salta, Argentina)AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 3 2010Fransisco R. Carnese Abstract Ancient DNA recovered from 21 individuals excavated from burial sites in the Pampa Grande (PG) region (Salta province) of North-Western Argentina (NWA) was analyzed using various genetic markers (mitochondrial DNA, autosomal STRs, and Y chromosomal STRs). The results were compared to ancient and modern DNA from various populations in the Andean and North Argentinean regions, with the aim of establishing their relationships with PG. The mitochondrial haplogroup frequencies described (11% A, 47% B, and 42% D) presented values comparable to those found for the ancient Andean populations from Peru and San Pedro de Atacama. On the other hand, mitochondrial and Y chromosomal haplotypes were specific to PG, as they did not match any other of the South American populations studied. The described genetic diversity indicates homogeneity in the genetic structure of the ancient Andean populations, which was probably facilitated by the intense exchange network in the Andean zone, in particular among Tiwanaku, San Pedro de Atacama, and NWA. The discovery of haplotypes unique to PG could be due to a loss of genetic diversity caused by recent events affecting the autochthonous populations (establishment of the Inca Empire in the region, colonization by the Europeans). Am J Phys Anthropol 2010. © 2009 Wiley-Liss, Inc. [source] Microbial community diversity associated with the intestinal mucosa of farmed rainbow trout (Oncoryhnchus mykiss Walbaum)AQUACULTURE RESEARCH, Issue 9 2009Daniel L Merrifield Abstract Bacterial communities from the intestinal tract of rainbow trout were investigated to assess transient and resident microbial communities using both culture-based and culture-independent techniques. Viable counts attached to the intestinal mucosa were in the range of log 4.77,5.38 and log 6.67,6.79 CFU g,1 in the intestinal contents. Pseudomonas spp. and Enterobacteriaceae constituted nearly 80% of the allochthonous population but <60% of the autochthonous populations. This coincided with an elevated mucosal level of a group of Gram-positive rods from ,2% in the digesta to 25,35% on the mucosa. This group was identified by 16S rRNA as Arthrobacter aurescens and Janibacter spp. HTCC2649. Analysis of denaturing gradient gel electrophoresis banding patterns showed complex communities in all intestinal regions. Similarity coefficients showed that mucosal communities were ,70% similar to digesta communities and yet due to the presence of bands found uniquely either in the digesta or on the mucosa, the communities are distinctly different. Scanning electron microscopy confirmed mucosal bacterial populations and highlighted a possible localized colonization between mucosal folds. The study highlights the complexity of resident microbial communities that have not been fully explored in previous rainbow trout studies; this is especially true with probiotic/prebiotic investigations. [source] | ||||||||||