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The western and eastern roots of the Saami--the story of genetic "outliers" told by mitochondrial DNA and Y chromosomes 下载免费PDF全文
Tambets K Rootsi S Kivisild T Help H Serk P Loogväli EL Tolk HV Reidla M Metspalu E Pliss L Balanovsky O Pshenichnov A Balanovska E Gubina M Zhadanov S Osipova L Damba L Voevoda M Kutuev I Bermisheva M Khusnutdinova E Gusar V Grechanina E Parik J Pennarun E Richard C Chaventre A Moisan JP Barác L Pericić M Rudan P Terzić R Mikerezi I Krumina A Baumanis V Koziel S Rickards O De Stefano GF Anagnou N Pappa KI Michalodimitrakis E Ferák V Füredi S Komel R Beckman L Villems R 《American journal of human genetics》2004,74(4):661-682
The Saami are regarded as extreme genetic outliers among European populations. In this study, a high-resolution phylogenetic analysis of Saami genetic heritage was undertaken in a comprehensive context, through use of maternally inherited mitochondrial DNA (mtDNA) and paternally inherited Y-chromosomal variation. DNA variants present in the Saami were compared with those found in Europe and Siberia, through use of both new and previously published data from 445 Saami and 17,096 western Eurasian and Siberian mtDNA samples, as well as 127 Saami and 2,840 western Eurasian and Siberian Y-chromosome samples. It was shown that the “Saami motif” variant of mtDNA haplogroup U5b is present in a large area outside Scandinavia. A detailed phylogeographic analysis of one of the predominant Saami mtDNA haplogroups, U5b1b, which also includes the lineages of the “Saami motif,” was undertaken in 31 populations. The results indicate that the origin of U5b1b, as for the other predominant Saami haplogroup, V, is most likely in western, rather than eastern, Europe. Furthermore, an additional haplogroup (H1) spread among the Saami was virtually absent in 781 Samoyed and Ob-Ugric Siberians but was present in western and central European populations. The Y-chromosomal variety in the Saami is also consistent with their European ancestry. It suggests that the large genetic separation of the Saami from other Europeans is best explained by assuming that the Saami are descendants of a narrow, distinctive subset of Europeans. In particular, no evidence of a significant directional gene flow from extant aboriginal Siberian populations into the haploid gene pools of the Saami was found. 相似文献
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Anmann T Eimre M Kuznetsov AV Andrienko T Kaambre T Sikk P Seppet E Tiivel T Vendelin M Seppet E Saks VA 《The FEBS journal》2005,272(12):3145-3161
The relationships between cardiac cell structure and the regulation of mitochondrial respiration were studied by applying fluorescent confocal microscopy and analysing the kinetics of mitochondrial ADP-stimulated respiration, during calcium-induced contraction in permeabilized cardiomyocytes and myocardial fibers, and in their 'ghost' preparations (after selective myosin extraction). Up to 3 microm free calcium, in the presence of ATP, induced strong contraction of permeabilized cardiomyocytes with intact sarcomeres, accompanied by alterations in mitochondrial arrangement and a significant decrease in the apparent K(m) for exogenous ADP and ATP in the kinetics of mitochondrial respiration. The V(max) of respiration showed a moderate (50%) increase, with an optimum at 0.4 microm free calcium and a decrease at higher calcium concentrations. At high free-calcium concentrations, the direct flux of ADP from ATPases to mitochondria was diminished compared to that at low calcium levels. All of these effects were unrelated either to mitochondrial calcium overload or to mitochondrial permeability transition and were not observed in 'ghost' preparations after the selective extraction of myosin. Our results suggest that the structural changes transmitted from contractile apparatus to mitochondria modify localized restrictions of the diffusion of adenine nucleotides and thus may actively participate in the regulation of mitochondrial function, in addition to the metabolic signalling via the creatine kinase system. 相似文献
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Excavating Y-chromosome haplotype strata in Anatolia 总被引:1,自引:0,他引:1
Cinnioğlu C King R Kivisild T Kalfoğlu E Atasoy S Cavalleri GL Lillie AS Roseman CC Lin AA Prince K Oefner PJ Shen P Semino O Cavalli-Sforza LL Underhill PA 《Human genetics》2004,114(2):127-148
Analysis of 89 biallelic polymorphisms in 523 Turkish Y chromosomes revealed 52 distinct haplotypes with considerable haplogroup substructure, as exemplified by their respective levels of accumulated diversity at ten short tandem repeat (STR) loci. The major components (haplogroups E3b, G, J, I, L, N, K2, and R1; 94.1%) are shared with European and neighboring Near Eastern populations and contrast with only a minor share of haplogroups related to Central Asian (C, Q and O; 3.4%), Indian (H, R2; 1.5%) and African (A, E3*, E3a; 1%) affinity. The expansion times for 20 haplogroup assemblages was estimated from associated STR diversity. This comprehensive characterization of Y-chromosome heritage addresses many multifaceted aspects of Anatolian prehistory, including: (1) the most frequent haplogroup, J, splits into two sub-clades, one of which (J2) shows decreasing variances with increasing latitude, compatible with a northward expansion; (2) haplogroups G1 and L show affinities with south Caucasus populations in their geographic distribution as well as STR motifs; (3) frequency of haplogroup I, which originated in Europe, declines with increasing longitude, indicating gene flow arriving from Europe; (4) conversely, haplogroup G2 radiates towards Europe; (5) haplogroup E3b3 displays a latitudinal correlation with decreasing frequency northward; (6) haplogroup R1b3 emanates from Turkey towards Southeast Europe and Caucasia and; (7) high resolution SNP analysis provides evidence of a detectable yet weak signal (<9%) of recent paternal gene flow from Central Asia. The variety of Turkish haplotypes is witness to Turkey being both an important source and recipient of gene flow. 相似文献
179.
We sought to distinguish between two potential effects of larval crowding on developmental schedules in Epirrita autumnata , an outbreaking folivorous moth. We asked if consequences of crowding can be entirely attributed to deterioration of environment, caused by mutual disturbance of larvae, or if there are specific modifications of reaction norms involved. In a laboratory rearing experiment, we found that most of the consequences of larval crowding could be explained as unspecific environmental effects. However, there was some evidence of crowding-related modifications of reaction norms. In particular, crowding during early development more strongly affected further growth of larvae than expected from the direct influence of inferior environmental quality: larvae crowded early in development had shorter growth periods in the final instar and attained lower final weights. It is not clear if these modifications of reaction norms are adaptive. Nevertheless, these observations document a type of plasticity which is different from unidimensional responses to variation in environmental quality, and may thus contribute to understanding evolution of body size in insects. However, recorded modifications of reaction norms are apparently weak enough to have only a minor role in population dynamics of E. autumnata . 相似文献
180.
Torroni A Bandelt HJ Macaulay V Richards M Cruciani F Rengo C Martinez-Cabrera V Villems R Kivisild T Metspalu E Parik J Tolk HV Tambets K Forster P Karger B Francalacci P Rudan P Janicijevic B Rickards O Savontaus ML Huoponen K Laitinen V Koivumäki S Sykes B Hickey E Novelletto A Moral P Sellitto D Coppa A Al-Zaheri N Santachiara-Benerecetti AS Semino O Scozzari R 《American journal of human genetics》2001,69(4):844-852
Mitochondrial HVS-I sequences from 10,365 subjects belonging to 56 populations/geographical regions of western Eurasia and northern Africa were first surveyed for the presence of the T-->C transition at nucleotide position 16298, a mutation which has previously been shown to characterize haplogroup V mtDNAs. All mtDNAs with this mutation were then screened for a number of diagnostic RFLP sites, revealing two major subsets of mtDNAs. One is haplogroup V proper, and the other has been termed "pre*V," since it predates V phylogenetically. The rather uncommon pre*V tends to be scattered throughout Europe (and northwestern Africa), whereas V attains two peaks of frequency: one situated in southwestern Europe and one in the Saami of northern Scandinavia. Geographical distributions and ages support the scenario that pre*V originated in Europe before the Last Glacial Maximum (LGM), whereas the more recently derived haplogroup V arose in a southwestern European refugium soon after the LGM. The arrival of V in eastern/central Europe, however, occurred much later, possibly with (post-)Neolithic contacts. The distribution of haplogroup V mtDNAs in modern European populations would thus, at least in part, reflect the pattern of postglacial human recolonization from that refugium, affecting even the Saami. Overall, the present study shows that the dissection of mtDNA variation into small and well-defined evolutionary units is an essential step in the identification of spatial frequency patterns. Mass screening of a few markers identified using complete mtDNA sequences promises to be an efficient strategy for inferring features of human prehistory. 相似文献