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Regine Hakenbeck - One of the best experts on this subject based on the ideXlab platform.

  • a global Gene Pool for high level cephalosporin resistance in commensal streptococcus species and streptococcus pneumoniae
    The Journal of Infectious Diseases, 1997
    Co-Authors: Peter Reichmann, Andrea Konig, Josefina Linares, Fernando Alcaide, Fred C Tenover, Linda K Mcdougal, Sonja Swidsinski, Regine Hakenbeck
    Abstract:

    : Highly penicillin- and cephalosporin-resistant Streptococcus mitis and Streptococcus oralis were isolated in Spain, Hungary, and Berlin. With chromosomal DNA of these strains, resistant transformants of Streptococcus pneumoniae were obtained that expressed low-affinity variants of penicillin-binding proteins (PBPs) 2x, 1a, 2a, and 2b in different combinations, depending on the selective conditions. The transformants had cefotaxime MICs of up to 6 microg/mL, and those with a low-affinity PBP 2b were highly deficient in penicillin-induced lysis. Sequence analysis of the pbp2x Genes confirmed the presence of a global Gene Pool of penicillin resistance determinants shared by commensal and pathogenic streptococci.

Steve Beebe - One of the best experts on this subject based on the ideXlab platform.

  • using molecular markers to assess the effect of introgression on quantitative attributes of common bean in the andean Gene Pool
    Theoretical and Applied Genetics, 2004
    Co-Authors: F Amirul M Islam, Steve Beebe, M Munoz, Joe Tohme, R J Redden, K E Basford
    Abstract:

    Progress in bean breeding programs requires the exploitation of Genetic variation that is present among races or through introgression across Gene Pools of Phaseolus vulgaris L. Of the two major common bean Gene Pools, the Andean Gene Pool seems to have a narrow Genetic base, with about 10% of the accessions in the CIAT core collection presenting evidence of introgression. The objective of this study was to quantify the degree of spontaneous introgression in a sample of common bean landraces from the Andean Gene Pool. The effects of introgression on morphological, economic and nutritional attributes were also investigated. HomoGeneity analysis was performed on molecular marker data from 426 Andean-type accessions from the primary centres of origin of the CIAT common bean core collection and two check varieties. Quantitative attribute diversity for 15 traits was studied based on the groups found from the cluster analysis of marker prevalence indices computed for each accession. The two-group summary consisted of one group of 58 accessions (14%) with low prevalence indices and another group of 370 accessions (86%) with high prevalence indices. The smaller group occupied the outlying area of points displayed from homoGeneity analysis, yet their geographic origin was widely distributed over the Andean region. This group was regarded as introgressed, since its accessions displayed traits that are associated with the Middle American Gene Pool: high resistance to Andean disease isolates but low resistance to Middle American disease isolates, low seed weight and high scores for all nutrient elements. Genotypes Generated by spontaneous introgression can be helpful for breeders to overcome the difficulties in transferring traits between Gene Pools.

  • Sources of Resistance to Colletotrichum lindemuthianum in the Secondary Gene Pool of Phaseolus vulgaris and in Crosses of Primary and Secondary Gene Pools.
    Plant Disease, 2002
    Co-Authors: George S. Mahuku, Carlos Jara, César Cajiao, Steve Beebe
    Abstract:

    Mahuku, G. S., Jara, C. E., Cajiao, C., and Beebe, S. 2002. Sources of resistance to Colletotrichum lindemuthianum in the secondary Gene Pool of Phaseolus vulgaris and in crosses of primary and secondary Gene Pools. Plant Dis. 86:1383-1387. Use of Genetic resistance is the most practical and economic way to manage anthracnose of common bean. Colletotrichum lindemuthianum, the causal agent of bean anthracnose, is a highly variabile pathogen, and there are no host resistance Genes that are effective against all known races of the pathogen. To diversify sources of resistance, we screened the core collection of the secondary Gene Pool of Phaseolus spp. and interspecific lines derived from simple and complex crosses of primary and secondary genotypes for their resistance to anthracnose. High levels of resistance were observed in the secondary Gene Pool. None of the 162 accessions tested was susceptible to C. lindemuthianum. Of the two species composing the secondary Gene Pool, P. polyanthus displayed higher levels of resistance than P. coccineus, and all accessions tested were resistant. The response of P. coccineus was more variable, with six genotypes showing an intermediate reaction. Among the 75 lines from interspecific crosses, 49 were resistant to the three races (races 6, 15, and 3481) used in this study, and higher levels of resistance were found in lines that had P. polyanthus as one of the parents in the crosses than in the lines derived from P. coccineus. These lines constitute a valuable source of resistance and may aid in the development of stable resistance to anthracnose.

E. V. Balanovskaya - One of the best experts on this subject based on the ideXlab platform.

  • The Gene Pool of Belgorod oblast population: study of biochemical Gene markers in populations of Ukraine and Belarus and the position of the Belgorod population in the Eastern Slavic Gene Pool system
    Russian Journal of Genetics, 2008
    Co-Authors: I. N. Lependina, Mikhail Churnosov, L. A. Atramentova, M. A. Ischuk, O. V. Tegako, L. I. Tegako, E. V. Balanovskaya
    Abstract:

    The characteristics of the Gene Pools of indigenous populations of Ukraine and Belarus have been studied using 28 alleles of 10 loci of biochemical Gene markers (HP, GC, TF, PI, C′3, ACP1, GLO1, PGM1, ESD, and 6-PGD). The Gene Pools of the Russian and Ukrainian indigenous populations of Belgorod oblast (Russia) and the indigenous populations of Ukraine and Belarus have been compared. Cluster analysis, multidimensional scaling, and factor analysis of the obtained data have been used to determine the position of the Belgorod population Gene Pool in the Eastern Slavic Gene Pool system.

  • The Russian Gene Pool: Gene Geography of Surnames
    Russian Journal of Genetics, 2001
    Co-Authors: Oleg Balanovsky, A. P. Buzhilova, E. V. Balanovskaya
    Abstract:

    Surnames are traditionally used in population Genetics as “quasi-Genetic” markers (i.e., analogs of Genes) when studying the structure of the Gene Pool and the factors of its microevolution. In this study, spatial variation of Russian surnames was analyzed with the use of computer-based Gene geography. Gene geography of surnames was demonstrated to be promising for population studies on the total Russian Gene Pool. Frequencies of surnames were studied in 64 sel'sovets (rural communities; a total of 33 thousand persons) of 52 raions (districts) of 22 oblasts (regions) of the European part of Russia. For each of 75 widespread surnames, an electronic map of its frequency was constructed. Summary maps of principal components were drawn based on all maps of individual surnames. The first 5 of 75 principal components accounted for half of the total variance, which indicates high resolving power of surnames. The map of the first principal component exhibits a trend directed from the northwestern to the eastern regions of the area studied. The trend of the second component was directed from the southwestern to the northern regions of the area studied, i.e., it was close to latitudinal. This trend almost coincided with the latitudinal trend of principal components for three sets of data (Genetic, anthropological, and dermatoglyphical). Therefore, the latitudinal trend may be considered the main direction of variation of the Russian Gene Pool. The similarity between the main scenarios for the Genetic and quasi-Genetic markers demonstrates the effectiveness of the use of surnames for analysis of the Russian Gene Pool. In view of the dispute between R. Sokal and L.L. Cavalli-Sforza about the effects of false correlations, the maps of principal components of Russian surnames were constructed by two methods: through analysis of maps and through direct analysis of original data on the frequencies of surnames. An almost complete coincidence of these maps (correlation coefficient ρ = 0.96) indicates that, taking into account the reliability of the data, the resultant maps of principal components have no errors of false correlations.

  • Computer technology of genogeographic analysis of a Gene Pool: II. Statistical transformation of maps
    Russian Journal of Genetics, 1994
    Co-Authors: E. V. Balanovskaya, S.d. Nurbaev, Yu. G. Rychkov
    Abstract:

    Transformations of computer maps of geographic distribution of Gene frequencies using basic mathematical statistical procedures are considered. These transformations are designated as statistical transformation of maps. Two transformation groups are considered: of one map separately and of a group of maps. Transformations possess a value beyond their use as intermediate stages of more complicated cartographical analysis: the resulting maps carry entirely new information on the geography of Genes or a Gene Pool. This article considers three examples of obtaining new Genetic profiles using statistical transformation algorithms. These profiles are of: (1) heterozygosity (of HLA-A, B, C loci in northeastern Eurasia); (2) disease risk (Rh-incompatibility of mother and child with simultaneous registration of Rh and ABO blood groups in Eastern Europe); (3) Genetic distances (from own mean ethnic values for Belarus and from mean Russian values for the Gene Pool of Eastern Europe). 15 refs., 9 figs., 1 tab.

Peter Reichmann - One of the best experts on this subject based on the ideXlab platform.

  • a global Gene Pool for high level cephalosporin resistance in commensal streptococcus species and streptococcus pneumoniae
    The Journal of Infectious Diseases, 1997
    Co-Authors: Peter Reichmann, Andrea Konig, Josefina Linares, Fernando Alcaide, Fred C Tenover, Linda K Mcdougal, Sonja Swidsinski, Regine Hakenbeck
    Abstract:

    : Highly penicillin- and cephalosporin-resistant Streptococcus mitis and Streptococcus oralis were isolated in Spain, Hungary, and Berlin. With chromosomal DNA of these strains, resistant transformants of Streptococcus pneumoniae were obtained that expressed low-affinity variants of penicillin-binding proteins (PBPs) 2x, 1a, 2a, and 2b in different combinations, depending on the selective conditions. The transformants had cefotaxime MICs of up to 6 microg/mL, and those with a low-affinity PBP 2b were highly deficient in penicillin-induced lysis. Sequence analysis of the pbp2x Genes confirmed the presence of a global Gene Pool of penicillin resistance determinants shared by commensal and pathogenic streptococci.

E V Balanovskaia - One of the best experts on this subject based on the ideXlab platform.

  • The Russian Gene Pool: Gene geography of Alu-insertions (ACE, APOA1, B65, PV92 TPA25)
    Molekuliarnaia biologiia, 2020
    Co-Authors: D S Solov'eva, M. A. Kuznetsova, E V Balanovskaia, O A Vasinskaia, S A Frolova, E A Pocheshkhova, I V Evseeva, M N Boldyreva, O P Balanovskiĭ
    Abstract:

    The analysis of five Alu insertion loci (ACE, AP4OA1, B65, PV92, TPA25) has been carried out for the first time in 10 Russian populations (1088 individuals), covered all parts of historical area of the Russian ethnos. Depending on locus, Russian populations exhibit similarity with their western (European populations) or with the eastern (populations of the Ural region) neighbors. Considering frequencies of the studied Alu-insertions, Russian Gene Pool exhibits low variation: average difference between populations is d = 0.007, whereas on classical markers, mtDNA and Y chromosome heteroGeneity of Russian Gene Pool is essentially higher (0.013, 0.033 and 0.142 respectively). Therefore, this set of five Alu insertions has lower variability on the intra-ethnic level. However in inter-ethnic comparisons the clear pattern was obtained: 13 Eastern European ethnic groups formed three clusters, according with their historical and geographical position--East Slavic, Caucasian and South Ural clusters. The obtained data confirms efficiency of using Alu insertions for studying Genetic differentiation and history of a Gene Pool of the Eastern European populations.

  • Computer technology for Genetic-geographical study of the Gene Pool. II. Statistical transformation of maps
    Genetika, 1994
    Co-Authors: E V Balanovskaia, S.d. Nurbaev, Iu G Rychkov
    Abstract:

    : Transformations of computer maps of geographical distribution of Gene frequencies using basic mathematical statistical procedures are considered. These transformations are designated as statistical transformation of maps. Two transformation groups are considered: of one map separately and of a group of maps. Transformations possess a value beyond their use as intermediate stages of more complicated cartographical analysis: the resulting maps carry entirely new information on the geography of Genes or a Gene Pool. This article considers three examples of obtaining new Genetic profiles using statistical transformation algorithms. These profiles are of: heterozygosity (of HLA-A, B, C loci in northeastern Eurasia); (2) disease risk (Rh-incompatibility of mother and child with simultaneous registration of Rh and ABO blood groups in Eastern Europe); (3) Genetic distances (from own mean ethnic values for Belarus' and from mean Russian values for the Gene Pool of Eastern Europe).

  • EthnoGenetics: adaptive structure of the Gene Pool of the mankind from the data on human polymorphic Genetic markers
    Genetika, 1990
    Co-Authors: E V Balanovskaia, Iu G Rychkov
    Abstract:

    : The mean FST value as a characteristic of Gene frequency changes in a random sample of polymorphic Genes from population Gene Pool provides the best indirect estimation of selectively neutral level of Genetic variability. The set of test criteria, including chi 2, F and t, can be used in order to compare F1 with F and subdivide Gene sample into three subgroups, or classes of Genes which are differing from each other by the degree of variation of allelic frequencies. These three classes comprise the adaptive structure of Gene Pool and consist of the Genes which are, respectively, under stabilizing and differentiating selection pressures or neutral ones. Adaptive structures of Gene Pools of aboriginal human populations at the main 9 geographical regions of the World, taken together, reveal statistically significantly correlation with adaptive structure of the total Gene Pool of the Mankind. But the correlation is rather small and therefore, the adaptive structure of human Gene Pool reveals between adaptive structures, the highest is for the USSR and the lowest are for the East-Asiatic and Australian regions. The proportion of neutral to non-neutral Genes is about 50% in the average, with the range of variation 40-60% in different regions. But none of the polymorphic Genes so far studied reveals constant neutrality in all regional conditions of environment and at different times of evolution history of human Gene Pool. Its adaptive structure underwent essential transformation from the Palaeolithic till the Postpalaeolithic times, but nevertheless, among the main features of contemporary adaptive structure of human Gene Pool, those predominate which are of the Palaeolithic origin.