| 1. |
- Green, Richard E., et al.
(författare)
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Three crocodilian genomes reveal ancestral patterns of evolution among archosaurs
- 2014
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Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 346:6215, s. 1335-
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Tidskriftsartikel (refereegranskat)abstract
- To provide context for the diversification of archosaurs-the group that includes crocodilians, dinosaurs, and birds-we generated draft genomes of three crocodilians: Alligator mississippiensis (the American alligator), Crocodylus porosus (the saltwater crocodile), and Gavialis gangeticus (the Indian gharial). We observed an exceptionally slow rate of genome evolution within crocodilians at all levels, including nucleotide substitutions, indels, transposable element content and movement, gene family evolution, and chromosomal synteny. When placed within the context of related taxa including birds and turtles, this suggests that the common ancestor of all of these taxa also exhibited slow genome evolution and that the comparatively rapid evolution is derived in birds. The data also provided the opportunity to analyze heterozygosity in crocodilians, which indicates a likely reduction in population size for all three taxa through the Pleistocene. Finally, these data combined with newly published bird genomes allowed us to reconstruct the partial genome of the common ancestor of archosaurs, thereby providing a tool to investigate the genetic starting material of crocodilians, birds, and dinosaurs.
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| 2. |
- Alfoeldi, Jessica, et al.
(författare)
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The genome of the green anole lizard and a comparative analysis with birds and mammals
- 2011
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 477:7366, s. 587-591
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Tidskriftsartikel (refereegranskat)abstract
- The evolution of the amniotic egg was one of the great evolutionary innovations in the history of life, freeing vertebrates from an obligatory connection to water and thus permitting the conquest of terrestrial environments(1). Among amniotes, genome sequences are available for mammals and birds(2-4), but not for non-avian reptiles. Here we report the genome sequence of the North American green anole lizard, Anolis carolinensis. We find that A. carolinensis microchromosomes are highly syntenic with chicken microchromosomes, yet do not exhibit the high GC and low repeat content that are characteristic of avian microchromosomes(2). Also, A. carolinensis mobile elements are very young and diverse-more so than in any other sequenced amniote genome. The GC content of this lizard genome is also unusual in its homogeneity, unlike the regionally variable GC content found in mammals and birds(5). We describe and assign sequence to the previously unknown A. carolinensis X chromosome. Comparative gene analysis shows that amniote egg proteins have evolved significantly more rapidly than other proteins. An anole phylogeny resolves basal branches to illuminate the history of their repeated adaptive radiations.
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| 3. |
- Berndt, Sonja I., et al.
(författare)
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Genome-wide association study identifies multiple risk loci for chronic lymphocytic leukemia
- 2013
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Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1061-4036 .- 1546-1718. ; 45:8, s. 868-U202
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Tidskriftsartikel (refereegranskat)abstract
- Genome-wide association studies (GWAS) have previously identified 13 loci associated with risk of chronic lymphocytic leukemia or small lymphocytic lymphoma (CLL). To identify additional CLL susceptibility loci, we conducted the largest meta-analysis for CLL thus far, including four GWAS with a total of 3,100 individuals with CLL (cases) and 7,667 controls. In the meta-analysis, we identified ten independent associated SNPs in nine new loci at 10q23.31 (ACTA2 or FAS (ACTA2/FAS), P = 1.22 x 10(-14)), 18q21.33 (BCL2, P = 7.76 x 10(-11)), 11p15.5 (C11orf21, P = 2.15 x 10(-10)), 4q25 (LEF1, P = 4.24 x 10(-10)), 2q33.1 (CASP10 or CASP8 (CASP10/CASP8), P = 2.50 x 10(-9)), 9p21.3 (CDKN2B-AS1, P = 1.27 x 10(-8)), 18q21.32 (PMAIP1, P = 2.51 x 10(-8)), 15q15.1 (BMF, P = 2.71 x 10(-10)) and 2p22.2 (QPCT, P = 1.68 x 10(-8)), as well as an independent signal at an established locus (2q13, ACOXL, P = 2.08 x 10(-18)). We also found evidence for two additional promising loci below genome-wide significance at 8q22.3 (ODF1, P = 5.40 x 10(-8)) and 5p15.33 (TERT, P = 1.92 x 10(-7)). Although further studies are required, the proximity of several of these loci to genes involved in apoptosis suggests a plausible underlying biological mechanism.
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| 4. |
- Jarvis, Erich D., et al.
(författare)
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Whole-genome analyses resolve early branches in the tree of life of modern birds
- 2014
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Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 346:6215, s. 1320-1331
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Tidskriftsartikel (refereegranskat)abstract
- To better determine the history of modern birds, we performed a genome-scale phylogenetic analysis of 48 species representing all orders of Neoaves using phylogenomic methods created to handle genome-scale data. We recovered a highly resolved tree that confirms previously controversial sister or close relationships. We identified the first divergence in Neoaves, two groups we named Passerea and Columbea, representing independent lineages of diverse and convergently evolved land and water bird species. Among Passerea, we infer the common ancestor of core landbirds to have been an apex predator and confirm independent gains of vocal learning. Among Columbea, we identify pigeons and flamingoes as belonging to sister clades. Even with whole genomes, some of the earliest branches in Neoaves proved challenging to resolve, which was best explained by massive protein-coding sequence convergence and high levels of incomplete lineage sorting that occurred during a rapid radiation after the Cretaceous-Paleogene mass extinction event about 66 million years ago.
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| 5. |
- Kita, Noriko T., et al.
(författare)
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Fall, classification, and exposure history of the Mifflin L5 chondrite
- 2013
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Ingår i: Meteoritics and Planetary Science. - : Wiley. - 1086-9379. ; 48:4, s. 641-655
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Tidskriftsartikel (refereegranskat)abstract
- The Mifflin meteorite fell on the night of April 14, 2010, in southwestern Wisconsin. A bright fireball was observed throughout a wide area of the midwestern United States. The petrography, mineral compositions, and oxygen isotope ratios indicate that the meteorite is a L5 chondrite fragmental breccia with light/dark structure. The meteorite shows a low shock stage of S2, although some shock-melted veins are present. The U,Th-He age is 0.7Ga, and the K-Ar age is 1.8Ga, indicating that Mifflin might have been heated at the time of the 470Ma L-chondrite parent body breakup and that U, Th-He, and K-Ar ages were partially reset. The cosmogenic radionuclide data indicate that Mifflin was exposed to cosmic rays while its radius was 3065cm. Assuming this exposure geometry, a cosmic-ray exposure age of 25 +/- 3Ma is calculated from cosmogenic noble gas concentrations. The low 22Ne/21Ne ratio may, however, indicate a two-stage exposure with a longer first-stage exposure at high shielding. Mifflin is unusual in having a low radiogenic gas content combined with a low shock stage and no evidence of late stage annealing; this inconsistency remains unexplained.
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