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F. BAGNOLI G. G. VENDRAMIN† A. BUONAMICI† A. G. DOULIS‡ S. C. GONZÁLEZ-MARTÍNEZ§ N. LA PORTA¶ D. MAGRI P. RADDI F. SEBASTIANI†† S. FINESCHI 《Molecular ecology》2009,18(10):2276-2286
This study represents the first large-scale analysis using nuclear molecular markers to assess genetic diversity and structure of Cupressus sempervirens L.. Genetic and fossil data were combined to infer the possible role of human activity and evolutionary history in shaping the diversity of cypress populations. We analysed 30 populations with six polymorphic nuclear microsatellite markers. Dramatic reductions in heterozygosity and allelic richness were observed from east to west across the species range. Structure analysis assigned individuals to two main groups separating central Mediterranean and eastern populations. The two main groups could be further divided into five subgroups which showed the following geographical distributions: Turkey with the Greek islands Rhodes and Samos, Greece (Crete), Southern Italy, Northern Italy, Tunisia with Central Italy. This pattern of genetic structure is also supported by samova and Barrier analyses. Palaeobotanical data indicated that Cupressus was present in Italy in the Pliocene, Pleistocene and Holocene. Furthermore, our molecular survey showed that Italian cypress populations experienced bottlenecks that resulted in reduced genetic diversity and allelic richness and greater genetic differentiation. Recent colonization or introduction may also have influenced levels of diversity detected in the Italian populations, as most individuals found in this range today have multilocus genotypes that are also present in the eastern range of the species. The data reveal a new interpretation of the history of cypress distribution characterized by ancient eastern populations (Turkey and Greek islands) and a mosaic of recently introduced trees and remnants of ancient, depauperate populations in the central Mediterranean range. 相似文献
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Comparison of Single and Touchdown PCR Protocols for Detecting Pneumocystis jirovecii DNA in Paraffin-Embedded Lung Tissue Samples 总被引:1,自引:0,他引:1
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M Trimborn T Liehr B Belitz L Pfeiffer R Varon H Neitzel H T?nnies 《The journal of histochemistry and cytochemistry》2005,53(3):351-354
We report on a balanced complex chromosomal aberration detected in a fetus after amniocentesis. The pregnancy was achieved after intracytoplasmic sperm injection. GTG-banding revealed a complex structurally rearranged karyotype with a translocation between chromosomes 5 and 15 and an additional paracentric inversion in the der(15) between bands 5q11.2 and 5q15. Ag-NOR staining showed an interstitial active nuclear organizer region in the der(15). Molecular cytogenetic analyses using whole-chromosome-painting probes, comparative genomic hybridization, and multicolor banding did not point to further structural aberrations or imbalances. Therefore, a complex rearrangement with three breakpoints has occurred, and the karyotype can be described as 46,XX,der(5)t(5;15) (q11.2;p12),der(15)t(5;15)(q11.2;p12)inv(5)(q11.2q15). 相似文献