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1.
Emily Olfson Catherine E. Cottrell Nicholas O. Davidson Christina A. Gurnett Jonathan W. Heusel Nathan O. Stitziel Li-Shiun Chen Sarah Hartz Rakesh Nagarajan Nancy L. Saccone Laura J. Bierut 《PloS one》2015,10(9)
The American College of Medical Genetics and Genomics (ACMG) recommends that clinical sequencing laboratories return secondary findings in 56 genes associated with medically actionable conditions. Our goal was to apply a systematic, stringent approach consistent with clinical standards to estimate the prevalence of pathogenic variants associated with such conditions using a diverse sequencing reference sample. Candidate variants in the 56 ACMG genes were selected from Phase 1 of the 1000 Genomes dataset, which contains sequencing information on 1,092 unrelated individuals from across the world. These variants were filtered using the Human Gene Mutation Database (HGMD) Professional version and defined parameters, appraised through literature review, and examined by a clinical laboratory specialist and expert physician. Over 70,000 genetic variants were extracted from the 56 genes, and filtering identified 237 variants annotated as disease causing by HGMD Professional. Literature review and expert evaluation determined that 7 of these variants were pathogenic or likely pathogenic. Furthermore, 5 additional truncating variants not listed as disease causing in HGMD Professional were identified as likely pathogenic. These 12 secondary findings are associated with diseases that could inform medical follow-up, including cancer predisposition syndromes, cardiac conditions, and familial hypercholesterolemia. The majority of the identified medically actionable findings were in individuals from the European (5/379) and Americas (4/181) ancestry groups, with fewer findings in Asian (2/286) and African (1/246) ancestry groups. Our results suggest that medically relevant secondary findings can be identified in approximately 1% (12/1092) of individuals in a diverse reference sample. As clinical sequencing laboratories continue to implement the ACMG recommendations, our results highlight that at least a small number of potentially important secondary findings can be selected for return. Our results also confirm that understudied populations will not reap proportionate benefits of genomic medicine, highlighting the need for continued research efforts on genetic diseases in these populations. 相似文献
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Angus Davison †§ Johnny D. S. Birks † Rachael C. Brookes † John E. Messenger† Huw I. Griffiths‡ 《Molecular ecology》2001,10(10):2479-2488
The flora and fauna of Europe are linked by a common biogeographic history, most recently the Pleistocene glaciations that restricted the range of most species to southern refugial populations. Changes in population size and migration, as well as selection, have all left a signature on the genetic differentiation. Thus, three paradigms of postglacial recolonization have been described, inferred from the patterns of DNA differentiation. Yet some species, especially wide-ranging carnivores, exhibit little population structuring between the proposed refugia, although relatively few have been studied due to the difficulty of obtaining samples. Therefore, we investigated mitochondrial variation in pine martens, Martes martes, in order to understand the extent to which they were affected by glacial cycles, and compared the results with an analysis of sequences from polecats, Mustela putorius. A general lack of ancient lineages, and a mismatch distribution that is consistent with an expanding population, is evidence that the present-day M. martes and Mu. putorius in central and northern Europe colonized from a single European refugium following a recent glaciation. There has also been interspecific mitochondrial introgression between M. martes and the sable M. zibellina in Fennoscandia. 相似文献
5.
Roger H. Brookes Michael C. Kew Arthur R. Rabson 《Cancer immunology, immunotherapy : CII》1987,25(2):149-152
Summary This study investigated the relation between the production of natural killer cytotoxic factors (NKCF) and the phenomenon of natural killing (NK) activity against target K562 cells. Two different models of defective NK cell activity were employed. In the first instance, cytotoxic activity of mononuclear cells (MN) derived from patients with hepatocellular carcinoma was compared to the ability of these cells to produce NKCF. Although direct cytotoxicity was considerably impaired in these patients, the ability of their MN to produce NKCF when stimulated with K562 cells was found to be normal. In the second model, MN treated with the lysosomotropic drug monensin showed considerably reduced direct cytotoxic activity, although they were capable of producing normal amounts of NKCF when activated by K562 cells. These results therefore indicate that there is no correlation between NK activity and corresponding NKCF release, and suggest that NKCF production and activity is independent of direct NK cytotoxic activity. 相似文献
6.
Neutral Amino Acid Transport in Astrocytes: Characterization of Na+ -Dependent and Na+ -Independent Components of α-Aminoisobutyric Acid Uptake 总被引:1,自引:0,他引:1
N. Brookes 《Journal of neurochemistry》1988,51(6):1913-1918
Neutral amino acid transport is largely unexplored in astrocytes, although a role for these cells in blood-brain barrier function is suggested by their close apposition to cerebrovascular endothelium. This study examined the uptake into mouse astrocyte cultures of alpha-aminoisobutyric acid (AIB), a synthetic model substrate for Na+-dependent system A transport. Na+-dependent uptake of AIB was characteristic of system A in its pH sensitivity, kinetic properties, regulatory control, and pattern of analog inhibition. The rate of system A transport declined markedly with increasing age of the astrocyte cultures. There was an unexpectedly active Na+-independent component of AIB uptake that declined less markedly than system A transport as culture age increased. Although the saturability of the Na+-independent component and its pattern of analog inhibition were consistent with system L transport, the following properties deviated: (1) virtually complete inhibition of Na+-independent AIB uptake by characteristic L system substrates, suggesting unusually high affinity of the transporter; (2) apparent absence of trans-stimulation of AIB influx; (3) unusually concentrative uptake at steady state (the estimated distribution ratio for 0.2 mM AIB was 55); and (4) susceptibility to inhibition by N-ethylmaleimide. Direct study of the uptake of system L substrates in astrocytes is needed to confirm the present indications of high affinity and concentrative Na+-independent transport. 相似文献
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8.
Emily L. Germain John W. Littlefield 《In vitro cellular & developmental biology. Plant》1986,22(2):107-112
Summary Stem cells of the embryonal carcinoma cell line called H6 can be induced to differnetiate to endoderm-like cells by retinoic
acid (3×10−6
M). We have detected a diffusible and stable factor which is secreted by H6 endoderm-like cells and stimulates the growth of
H6 stem cells. The stimulation by the endoderm-like cells is considereably greater than that by mouse fibroblasts or H6 stem
cells themselves. No reciprocal stimulation of endoderm-like cells by stem cells occurs. Part but not all of the stimulation
might be due to extracellular matrix proteins or to insulin-like growth factor type 2, each of which also stimulates the growth
of H6 stem cells. Insulin causes no such stimulation.
This work was supported by research rant no. CA-16754 from the National Cancer Institute to J. W. L. E. L. G. was supported
by an American Heart Association Medical Student Research Award.
Editor's Statement This paper presents a good example of cooperativity between undifferentiated teratoma stem cells and differentiated
parietal endoderm-derived countrparts in terms of growth support. It raises the interesting question of the relationship between
factors produced by paprietal and visceral endoderm cells. Gordon H. Sato 相似文献
9.
Sicyos motozintlensis is described from the vicinity of Motozintla de Mendoza, Chiapas. It shows a strong similarity toS. chiriquensis Hammel & D’Arcy from Panama. 相似文献
10.
CHORIZOCOCCUS HERBICOLA (MASKELL) (COMB. N): (HOMOPTERA: PSEUDOCOCCIDAE) A GRASS-INFESTING SPECIES IN AUSTRALIA 总被引:1,自引:1,他引:0
i
The Maskell species Dactylopius herbicola , a mealybug infesting grass in Australia, is redescribed and designated as a new combination, Chorizococcus herbicola (Maskell). 相似文献
The Maskell species Dactylopius herbicola , a mealybug infesting grass in Australia, is redescribed and designated as a new combination, Chorizococcus herbicola (Maskell). 相似文献