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21.
Rhett P. Ketterling Cynthia D. K. Bottema Dwight D. Koeberl Setsuko Ii Steve S. Sommer 《Human genetics》1991,87(3):333-337
Summary By direct genomic sequencing, we have delineated the causative mutation in 64 families of European descent with hemophilia B. Six (9%) had a CT transition at base 31008, which substitutes methionine for threonine 296 (T296M) in the catalytic domain of factor IX. Five of the patients had the same haplotype (frequency of 16% in the northern European population). These individuals are of Amish/German descent and they are likely to share a common ancestor. The sixth patient had a different haplotype, which indicates that his mutation had an independent origin. The data highlight the importance of clinical criteria for the classification of hemophilia B. All six patients had clinically mild disease and their factor IX coagulant activities were in the range of 3%–6% when tested simultaneously in one laboratory, yet the factor IX activities provided with patient records varied 40-fold. Due to the high frequency of this mutation, we have utilized the technique of polymerase chain reaction amplification of specific alleles (PASA) to perform rapid and inexpensive carrier diagnoses in the families with this mutation. This is of particular importance for the Amish since the mutation should account for much of, if not all, the mild hemophilia B that is commonly found in this population. 相似文献
22.
Various nystatin-resistant mutants defective in S-adenosylmethionine: delta 24-sterol-C-methyltransferase (EC 2.1.1.41) were shown to possess alleles of the same gene, erg6. The genetic map location of erg6 was shown to be close to trp1 on chromosome 4. Despite the single locus for erg6, S-adenosylmethionine: delta 24-sterol-C-methyltransferase enzyme activity was found in three separate fractions: mitochondria, microsomes, and the "floating lipid layer." The amount of activity in each fraction could be manipulated by assay conditions. The lipids and lipid synthesis of mutants of Saccharomyces cerevisiae defective in the delta 24-sterol-C-methyltransferase were compared with a C5(6) desaturase mutant and parental wild types. No ergosterol (C28 sterol) could be detected in whole-cell sterol extracts of the erg6 mutants, the limits of detection being less than 10(-11) mol of ergosterol per 10(8) cells. The distribution of accumulated sterols by these mutants varied with growth phase and between free and esterified fractions. The steryl ester concentrations of the mutants were eight times higher than those of the wild type from exponential growth samples. However, the concentration of the ester accumulated by the mutants was not as great in stationary-phase cells. Whereas the head group phospholipid composition was the same between parental and mutant strains, strain-dependent changes in fatty acids were observed, most notably a 40% increase in the oleic acid content of phosphatidylethanolamine of one erg6 mutant, JR5. 相似文献
23.
Comparative Genome Organization of Vertebrates 总被引:13,自引:0,他引:13
L. Andersson A. Archibald M. Ashburner S. Audun W. Barendse J. Bitgood C. Bottema T. Broad S. Brown D. Burt C. Charlier N. Copeland S. Davis M. Davisson J. Edwards A. Eggen G. Elgar J. T. Eppig I. Franklin P. Grewe T. Gill J. A. M. Graves R. Hawken J. Hetzel A. Hilyard H. Jacob L. Jaswinska N. Jenkins H. Kunz G. Levan O. Lie L. Lyons P. Maccarone C. Mellersh G. Montgomery S. Moore C. Moran D. Morizot M. Neff F. Nicholas S. O’Brien Y. Parsons J. Peters J. Postlethwait M. Raymond M. Rothschild L. Schook Y. Sugimoto C. Szpirer M. Tate J. Taylor J. VandeBerg M. Wakefield J. Wienberg J. Womack 《Mammalian genome》1996,7(10):717-734
24.
C. A. Morris W. S. Pitchford N. G. Cullen A. K. Esmailizadeh S. M. Hickey D. Hyndman K. G. Dodds R. A. Afolayan A. M. Crawford‡ C. D. K. Bottema 《Animal genetics》2009,40(5):648-654
A quantitative trait locus (QTL) study was carried out in two countries, recording live animal and carcass composition traits. Back-cross calves (385 heifers and 398 steers) were generated, with Jersey and Limousin breed backgrounds. The New Zealand cattle were reared on pasture to carcass weights averaging 229 kg, whilst the Australian cattle were reared on grass and finished on grain (for at least 180 days) to carcass weights averaging 335 kg. From 11 live animal traits and 31 carcass composition traits respectively, 5 and 22 QTL were detected in combined-sire analyses, which were significant ( P < 0.05) on a genome-wise basis. Fourteen significant traits for carcass composition QTL were on chromosome 2 and these were traits associated with muscling and fatness. This chromosome carried a variant myostatin allele (F94L), segregating from the Limousin ancestry. Despite very different cattle management systems between the two countries, the two populations had a large number of QTL in common. Of the 18 traits which were common to both countries, and which had significant QTL at the genome-wise level, eight were significant in both countries. 相似文献
25.
Background
A haplotype approach to genomic prediction using high density data in dairy cattle as an alternative to single-marker methods is presented. With the assumption that haplotypes are in stronger linkage disequilibrium (LD) with quantitative trait loci (QTL) than single markers, this study focuses on the use of haplotype blocks (haploblocks) as explanatory variables for genomic prediction. Haploblocks were built based on the LD between markers, which allowed variable reduction. The haploblocks were then used to predict three economically important traits (milk protein, fertility and mastitis) in the Nordic Holstein population.Results
The haploblock approach improved prediction accuracy compared with the commonly used individual single nucleotide polymorphism (SNP) approach. Furthermore, using an average LD threshold to define the haploblocks (LD≥0.45 between any two markers) increased the prediction accuracies for all three traits, although the improvement was most significant for milk protein (up to 3.1 % improvement in prediction accuracy, compared with the individual SNP approach). Hotelling’s t-tests were performed, confirming the improvement in prediction accuracy for milk protein. Because the phenotypic values were in the form of de-regressed proofs, the improved accuracy for milk protein may be due to higher reliability of the data for this trait compared with the reliability of the mastitis and fertility data. Comparisons between best linear unbiased prediction (BLUP) and Bayesian mixture models also indicated that the Bayesian model produced the most accurate predictions in every scenario for the milk protein trait, and in some scenarios for fertility.Conclusions
The haploblock approach to genomic prediction is a promising method for genomic selection in animal breeding. Building haploblocks based on LD reduced the number of variables without the loss of information. This method may play an important role in the future genomic prediction involving while genome sequences. 相似文献26.
Trace metal (Zn, Pb, Cu, Cr and Cd) concentrations in the water column and in the liver, muscle and gill tissues of Parachanna obscura and Clarias gariepinus in Agulu Lake, Nigeria, were investigated in June 2014 and compared with WHO and FAO safe limits for water and fish. Hazard index (HI) values were estimated to assess the potential public health risk of consuming contaminated fish. Lead and cadmium exceeded WHO guideline values for drinking water. In most cases, variations in concentration of the metals in organs were liver > muscle > gill. Differences in tissue-specific concentrations between species were not significant, except for zinc in muscles and gills. Cadmium and chromium were not detected in the fish, but lead was above the FAO maximum value for consumption. Hazard index values were below 1, indicating a low risk to public health. However, trace metal contamination in Agulu Lake is increasing. 相似文献
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29.
The results are discussed of the palynological (pollen-analytical) examination of a sediment section in the Hula Valley of
northern Israel, with evidence of Acheulian occupation dated to 700,000–800,000 b.p. In general there is a fair agreement between the palynological data and the wood remains identified from the site, but there
are also discrepancies, some of which can be explained and others not. Although relatively well represented in the pollen
record, Pinus (pine) most probably did not occur in the Hula area. Some pollen types are thought to have been carried in from hundreds
of kilometres away (long-distance transport). Together the pollen and wood evidence suggests that Quercus
ithaburensis–Pistacia
atlantica (Tabor oak–Atlantic terebinth) woodland (open forest) was found in the Hula Valley (other than the lake and marshes) and
on the lower reaches of the mountains flanking the valley on both sides. In addition to deciduous Tabor oak, evergreen Kermes
oak (Quercus
calliprinos) must have been an important component of this woodland. Wild olive (Olea
europaea var. oleaster) may also have been quite common here. The suggestion of open forest, with fairly widely spaced trees, is based upon the
high non-arboreal pollen frequencies and indicates fairly dry climatic conditions. Various stream-bank trees and shrubs are
represented in the pollen and/or wood records, such as Fraxinus (ash), Ulmus (elm), Salix (willow) and Platanus (plane tree). During the period represented by the upper section of the pollen diagram, Cedrus (cedar) must have reached the Hula area, indicating increased humidity. In the steppe-like field layer (undergrowth of the
woodland) grasses (Gramineae) must have played a prominent role in addition to a great number of other species. In particular
Compositae and Umbelliferae include a large variety of species (many different pollen types). Two Chenopodiaceae maxima, coinciding
with Gramineae minima, are thought to be indicative of periods of increased climatic dryness. The local lake and marsh vegetation
is fairly well represented in the pollen record, but interpretation in terms of vegetation succession is only possible to
some degree. Mention is made here of Trapa natans (water chestnut), the nuts of which were consumed by the Acheulian inhabitants.
Sytze Bottema: Deceased in 2005. 相似文献
30.
Didier F. Pisani Cynthia D.K. Bottema Christian Dani 《Biochemical and biophysical research communications》2010,396(3):767-773
Fat cell accumulation in skeletal muscle is a major characteristic of various disorders, such as obesity, sarcopenia and dystrophies. Moreover, these fat cells could be involved in muscle homeostasis regulation as previously described for adipocytes in bone marrow. Despite recent advances on the topic, no clearly characterized mouse model is currently available to study fat accumulation within skeletal muscle. Here, we report a detailed characterization of a mouse model of skeletal muscle fat cell accumulation after degeneration induced by intra-muscular injection of glycerol. Information is provided on the kinetics of degeneration/fat deposition, including the quantity of fat deposited based on various parameters such as glycerol concentration, age, sex and strain of mice. Finally, these fat cells are characterized as true white adipocytes morphologically and molecularly. Our study shows that the mouse adipocyte accumulation within skeletal muscle after glycerol degeneration is a reproducible, transposable and easy model to use. This mouse model should allow a more comprehensive understanding of the impact of adipocyte accumulation in skeletal muscle pathophysiology. 相似文献