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The effect of a segregating economic trait locus (ETL) can be detected with the aid of a linked genetic marker, if specific alleles of each locus are in association among the individuals genotyped for the genetic marker. For dairy cattle this can be achieved by application of the ‘granddaughter design’. If only the sires and their sons are genotyped for the genetic markers, then the allele origin of sons having the same genotypes as their sires cannot be determined. Seven sires and 101 sons were genotyped for five microsatellites. The mean frequency of heterozygous sires was 77%. The mean number of alleles per locus was 8.2. Frequency of informative sons per locus ranged from 60% to 80% with a mean of 72%. With highly polymorphic microsatellites, at least 60% more grandsire families can be included in the analysis, and the number of sons assayed can be reduced by 40%, as compared to diallelic markers. 相似文献
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《Acta Genetica Sinica》2010,(3)
The domestication of cattle fuelled the development of agricultural society in the history of human being.The evolution and genetic relationship of cattle can be elucidated by investigating the variation of mitochondrial DNA(mtDNA) D-loop sequence.In this study,we built a cattle phylogeny with a pool of 856 individual D-loop sequences,of which 264 Chinese cattle D-loop sequences were obtained in this study(141 ones were first analyzed,and 123 were first submitted) and the rest sequences of cattle from six A... 相似文献
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Sign language studies of cross-fostered chimpanzees measure the effect of special rearing conditions on the development of
very young chimpanzees. Cross-fostered chimpanzees, like human children, develop gradually in a process that takes many years.
Here we discuss details of the procedure, the overlap between human and chimpanzee infants in the contents of the first 50-item
vocabularies, and the ways in which the signs of the chimpanzees exhibit the fuzziness of natural language categories. We
also compare the cross-fostering approach with more traditional modular approaches to the study of language-like behavior
in nonhuman animals.
Project Washoe was originally supported by grants MH-12154 from the National Institute of Mental Health and GB-7432 from the
National Science Foundation. We gratefully acknowledge this support and the support that later sign language studies of chimpanzees
have received since then from NIH, NSF, the National Geographic Society, the Grant Foundation, the Spencer Foundation, the
University of Nevada, and the UNR Foundation. 相似文献
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Debating Eukaryogenesis—Part 2: How Anachronistic Reasoning Can Lure Us into Inventing Intermediates
Dave Speijer 《BioEssays : news and reviews in molecular, cellular and developmental biology》2020,42(5):1900153
Eukaryotic origins are inextricably linked with the arrival of a pre-mitochondrion of alphaproteobacterial-like ancestry. However, the nature of the “host” cell and the mode of entry are subject to heavy debate. It is becoming clear that the mutual adaptation of a relatively simple, archaeal host and the endosymbiont has been the defining influence at the beginning of the eukaryotic lineage; however, many still resist such symbiogenic models. In part 1, it is posited that a symbiotic stage before uptake (“pre-symbiosis”) seems essential to allow further metabolic integration of the two partners ending in endosymbiosis. Thus, the author argued against phagocytic mechanisms (in which the bacterium is prey or parasite) as the mode of entry. Such positions are still broadly unpopular. Here it is explained why. Evolutionary thinking, especially in the case of eukaryogenesis, is still dominated by anachronistic reasoning, in which highly derived protozoan organisms are seen as in some way representative of intermediate steps during eukaryotic evolution, hence poisoning the debate. This reasoning reflects a mind-set that ignores that Darwinian evolution is a fundamentally historic process. Numerous examples of this kind of erroneous reasoning are given, and some basic precautions against its use are formulated. Also see the video abstract here https://youtu.be/ekqtNleVJpU 相似文献
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E.M. del Campo A. del Hoyo C. Royo L.M. Casano R. lvarez E. Barreno 《Molecular phylogenetics and evolution》2010,57(3):1323-1328