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71.
Detection of genotyping errors and integration of such errors in statistical analysis are relatively neglected topics, given their importance in gene mapping. A few inopportunely placed errors, if ignored, can tremendously affect evidence for linkage. The present study takes a fresh look at the calculation of pedigree likelihoods in the presence of genotyping error. To accommodate genotyping error, we present extensions to the Lander-Green-Kruglyak deterministic algorithm for small pedigrees and to the Markov-chain Monte Carlo stochastic algorithm for large pedigrees. These extensions can accommodate a variety of error models and refrain from simplifying assumptions, such as allowing, at most, one error per pedigree. In principle, almost any statistical genetic analysis can be performed taking errors into account, without actually correcting or deleting suspect genotypes. Three examples illustrate the possibilities. These examples make use of the full pedigree data, multiple linked markers, and a prior error model. The first example is the estimation of genotyping error rates from pedigree data. The second-and currently most useful-example is the computation of posterior mistyping probabilities. These probabilities cover both Mendelian-consistent and Mendelian-inconsistent errors. The third example is the selection of the true pedigree structure connecting a group of people from among several competing pedigree structures. Paternity testing and twin zygosity testing are typical applications. 相似文献
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Brian E. Roe Michael R. Tilley Howard H. Gu David Q. Beversdorf Wolfgang Sadee Timothy C. Haab Audrey C. Papp 《PloS one》2009,4(8)
With recent advances in understanding of the neuroscience of risk taking, attention is now turning to genetic factors that may contribute to individual heterogeneity in risk attitudes. In this paper we test for genetic associations with risk attitude measures derived from both the psychology and economics literature. To develop a long-term prospective study, we first evaluate both types of risk attitudes and find that the economic and psychological measures are poorly correlated, suggesting that different genetic factors may underlie human response to risk faced in different behavioral domains. We then examine polymorphisms in a spectrum of candidate genes that affect neurotransmitter systems influencing dopamine regulation or are thought to be associated with risk attitudes or impulsive disorders. Analysis of the genotyping data identified two single nucleotide polymorphisms (SNPs) in the gene encoding the alpha 4 nicotine receptor (CHRNA4, rs4603829 and rs4522666) that are significantly associated with harm avoidance, a risk attitude measurement drawn from the psychology literature. Novelty seeking, another risk attitude measure from the psychology literature, is associated with several COMT (catechol-O-methyl transferase) SNPs while economic risk attitude measures are associated with several VMAT2 (vesicular monoamine transporter) SNPs, but the significance of these associations did not withstand statistical adjustment for multiple testing and requires larger cohorts. These exploratory results provide a starting point for understanding the genetic basis of risk attitudes by considering the range of methods available for measuring risk attitudes and by searching beyond the traditional direct focus on dopamine and serotonin receptor and transporter genes. 相似文献
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Molecular and cytogenetic analyses of stably and unstably expressed transgene loci in tobacco. 总被引:17,自引:0,他引:17 下载免费PDF全文
V A Iglesias E A Moscone I Papp F Neuhuber S Michalowski T Phelan S Spiker M Matzke A J Matzke 《The Plant cell》1997,9(8):1251-1264
To study the influence of genomic context on transgene expression, we have determined the T-DNA structure, flanking DNA sequences, and chromosomal location of four independent transgene loci in tobacco. Two of these loci were stably expressed in the homozygous condition over many generations, whereas the other two loci became unstable after several generations of homozygosity. The stably expressed loci comprised relatively simple T-DNA arrangements that were flanked on at least one side by plant DNA containing AT-rich regions that bind to nuclear matrices in vitro. Of the unstably expressed loci, one consisted of multiple incomplete T-DNA copies, and the second contained a single intact T-DNA; in both cases, however, binary vector sequences were directly contiguous to a right T-DNA border. Fluorescence in situ hybridization demonstrated that the two stably expressed inserts were present in the vicinity of telomeres. The two unstably expressed inserts occupied intercalary and paracentromeric locations, respectively. Results on the stability of transgene expression in F1 progeny obtained by intercrossing the four lines and the sensitivity of the four transgene loci to inactivation in the presence of an unlinked "trans-silencing" locus are also presented. The findings are discussed in the context of repetitive DNA sequences and the allotetraploid nature of the tobacco genome. 相似文献
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Zs Gy. Papp M. Saroglia Zs. Jeney G. Jeney G. Terova 《Zeitschrift fur angewandte Ichthyologie》1999,15(4-5):258-260
The aim of this study was to determine the vitamin C status of various tissues, and collagen concentration in cartilage, of a sterlet ( Acipenser ruthenus L.) x Siberian sturgeon ( Acipenser baerii Brandt) hybrid fed different dietary vitamin C rations. Growth, vitamin C status and collagen concentration were measured in groups fed diets supplemented with 150, 300, 600 mg.kg-1 ascorbate-2-polyphosphate (APP); 100, 200, 400 mg.kg-1 ascorbate-2-monophosphate (AMP), 1000 mg.kg-1 L-ascorbic acid (AA) and with an almost ascorbate free diet (Total AA > 5 mg.kg-1 ), as a control.
No significant differences in growth were observed, and no external symptoms of scurvy developed in the vitamin C-free group. No reduction in total vitamin C concentration was revealed in the tissues examined, as compared with initial concentrations. Ascorbate-2-phosphate esters were only found in kidney or hepatopancreas of fish fed with these vitamin C derivatives. Significantly (p<0.05) lower contents of collagen were observed in the control group after 8 weeks feeding. No significant differences were found among the groups after 16 weeks although the collagen concentration in the cartilage was slightly lower in the control group without vitamin C supplementation. 相似文献
No significant differences in growth were observed, and no external symptoms of scurvy developed in the vitamin C-free group. No reduction in total vitamin C concentration was revealed in the tissues examined, as compared with initial concentrations. Ascorbate-2-phosphate esters were only found in kidney or hepatopancreas of fish fed with these vitamin C derivatives. Significantly (p<0.05) lower contents of collagen were observed in the control group after 8 weeks feeding. No significant differences were found among the groups after 16 weeks although the collagen concentration in the cartilage was slightly lower in the control group without vitamin C supplementation. 相似文献
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Rita Papp Glenna C. L. Bett Agnieszka Lis Randall L. Rasmusson István Baczkó András Varró Guy Salama 《Biology of sex differences》2017,8(1):26