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Yanhua Qu Chunhai Chen Ying Xiong Huishang She Yong E Zhang Yalin Cheng Shane DuBay Dongming Li Per G P Ericson Yan Hao Hongyuan Wang Hongfeng Zhao Gang Song Hailin Zhang Ting Yang Chi Zhang Liping Liang Tianyu Wu Jinyang Zhao Qiang Gao Weiwei Zhai Fumin Lei 《国家科学评论(英文版)》2020,7(1):113
Known as the ‘third polar region’, the Qinghai-Tibet Plateau represents one of the harshest highland environments in the world and yet a number of organisms thrive there. Previous studies of birds, animals and humans have focused on well-differentiated populations in later stages of phenotypic divergence. The adaptive processes during the initial phase of highland adaptation remain poorly understood. We studied a human commensal, the Eurasian Tree Sparrow, which has followed human agriculture to the Qinghai-Tibet Plateau. Despite strong phenotypic differentiation at multiple levels, in particular in muscle-related phenotypes, highland and lowland populations show shallow genomic divergence and the colonization event occurred within the past few thousand years. In a one-month acclimation experiment investigating phenotypic plasticity, we exposed adult lowland tree sparrows to a hypoxic environment and did not observe muscle changes. Through population genetic analyses, we identified a signature of polygenic adaptation, whereby shifts in allele frequencies are spread across multiple loci, many of which are associated with muscle-related processes. Our results reveal a case of positive selection in which polygenic adaptation appears to drive rapid phenotypic evolution, shedding light on early stages of adaptive evolution to a novel environment. 相似文献
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Sanju Jalla Sunil Sazawal Salkat Deb robert E. Black Satya Narayan Das Archana Sarkar Maharaj K. Bhan 《Indian journal of clinical biochemistry : IJCB》2004,19(2):95-99
Lymphocyte subset estimations by flow cytometry in population-based studies require transportation of samples from the field
site to the laboratory. As samples arrive late in the day they have to wait overnight before being processed. The effect of
two possible approaches, sample storage for 24 h before staining and immediate staining with analysis after 24 h and 48 h
were evaluated. Two sets of experiments were performed with EDTA (ethylenediamine tetra-acetate) anticoagulated peripheral
blood. In the first experiment, after collection, each sample was divided into two portions. One portion was stained at the
time of blood collection and the other 24 h later after keeping it at room temperature (38–45°C). In the second experiment,
blood samples were stained within 1–2 h. Each sample was analyzed immediately upon completion of staining process and subsequently
after 24 h and 48 h of storage at 4°C. Results suggest that blood collected in EDTA can be processed using whole blood lysis
method, after storage at room temperature (38–45°C) for 24 h with some but not significant alteration in T-cell subsets. Storage
at 4°C after staining for 24 h results in a lesser and insignificant loss of cells or alteration of T-cell subsets and may
be the method of choice. 相似文献
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David C. Hughes Stephen H. Day Ildus I. Ahmetov Alun G. Williams 《Journal of sports sciences》2013,31(13):1425-1434
Abstract Environmental and genetic factors influence muscle function, resulting in large variations in phenotype between individuals. Multiple genetic variants (polygenic in nature) are thought to influence exercise-related phenotypes, yet how the relevant polymorphisms combine to influence muscular strength in individuals and populations is unclear. In this analysis, 22 genetic polymorphisms were identified in the literature that have been associated with muscular strength and power phenotypes. Using typical genotype frequencies, the probability of any given individual possessing an “optimal” polygenic profile was calculated as 0.0003% for the world population. Future identification of additional polymorphisms associated with muscular strength phenotypes would most likely reduce that probability even further. To examine the genetic potential for muscular strength within a human population, a “total genotype score” was generated for each individual within a hypothetical population of one million. The population expressed high similarity in polygenic profile with no individual differing by more than seven genotypes from a typical profile. Therefore, skeletal muscle strength potential within humans appears to be limited by polygenic profile similarity. Future research should aim to replicate more genotype–phenotype associations for muscular strength, because only five common genetic polymorphisms identified to date have positive replicated findings. 相似文献
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