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Highly Significant Association (highly + significant_association)
Selected AbstractsAssociations of simple sequence repeats with quantitative trait variation including biotic and abiotic stress tolerance in Hordeum spontaneumPLANT BREEDING, Issue 4 2003V. Ivandic abstract A total of 33 simple sequence repeats (SSRs) was analyzed in 52 genotypes of Hordeum spontaneum originally collected from two different soil types (Terra rossa and Basalt) at Tabigha in Israel. Data on the performance of developmental, morphological, and yield-related traits under well-watered control and water-stress conditions were available from previous experimentation, and powdery mildew susceptibility was scored. Regression analyses based on SSR allele class differences were performed. Highly significant associations were detected at the SSR loci Bmac181 (on chromosome 4H) and Bmac316 (6H) for water -stress tolerance and powdery mildew resistance, respectively. The study shows that association mapping using SSRs and genetically diverse germplasm provides an effective means of relating genotypes to complex quantitative phenotypes. [source] Psychosis and offending in British Columbia: characteristics of a secure hospital populationCRIMINAL BEHAVIOUR AND MENTAL HEALTH, Issue 3 2001Nicola Hodelet Specialist Registrar Introduction There is an increased likelihood of violence in the mentally ill although the risk is small. Aims The study aimed to ascertain the features in a secure hospital population that linked offending and mental illness. Method A survey of patients in the high security hospital serving the province of British Columbia in Canada was carried out. Information on 175 mentally disordered offenders was extracted and included demographic data and specific characteristics of their offences, diagnoses and psychotic symptoms. Results The most prevalent offences were crimes of violence, but 39% of patients were not primarily violent offenders. Almost two-thirds (61%) had two or more diagnoses. A large majority of the patients were psychotic, schizophrenia being the most common diagnosis. There was a highly significant association between psychosis and violence, but the strength of the association was not increased by the presence of imperative hallucinations or delusions. The sample comprised various ethnic groups, one of which, Native Americans, was over-represented. However, no association was found between violent offending and ethnicity, or age or years of illness. Discussion The study replicates previous findings of the link between violent offending and psychosis, but not a specific link between violent offending and psychotic drive. A surprising finding was a lack of association between violent offences and substance misuse. Copyright © 2001 Whurr Publishers Ltd. [source] Association between the CHRM2 gene and intelligence in a sample of 304 Dutch familiesGENES, BRAIN AND BEHAVIOR, Issue 8 2006M. F. Gosso The CHRM2 gene is thought to be involved in neuronal excitability, synaptic plasticity and feedback regulation of acetylcholine release and has previously been implicated in higher cognitive processing. In a sample of 667 individuals from 304 families, we genotyped three single-nucleotide polymorphisms (SNPs) in the CHRM2 gene on 7q31,35. From all individuals, standardized intelligence measures were available. Using a test of within-family association, which controls for the possible effects of population stratification, a highly significant association was found between the CHRM2 gene and intelligence. The strongest association was between rs324650 and performance IQ (PIQ), where the T allele was associated with an increase of 4.6 PIQ points. In parallel with a large family-based association, we observed an attenuated , although still significant , population-based association, illustrating that population stratification may decrease our chances of detecting allele,trait associations. Such a mechanism has been predicted earlier, and this article is one of the first to empirically show that family-based association methods are not only needed to guard against false positives, but are also invaluable in guarding against false negatives. [source] Cyclooxygenase-2 expression correlates with phaeochromocytoma malignancy: evidence for a Bcl-2-dependent mechanismHISTOPATHOLOGY, Issue 6 2007I S Cadden Aims:, Phaeochromocytomas are rare but potentially life-threatening neuroendocrine tumours of the adrenal medulla or sympathetic nervous system ganglia. There are no histological features which reliably differentiate benign from malignant phaeochromocytomas. The aim of the study was to evaluate cyclooxygenase (COX)-2 and Bcl-2 as tissue-based biomarkers of phaeochromocytoma prognosis. Methods and results:, COX-2 and Bcl-2 expression were examined immunohistochemically in tissue from 41 sporadic phaeochromocytoma patients followed up for a minimum of 5 years after diagnosis. There was a statistically significant association between COX-2 histoscore (intensity × proportion) and the development of tumour recurrence or metastases (P = 0.006). A significant relationship was observed between coexpression of COX-2 and Bcl-2 in the primary tumour and the presence of recurrent disease (P = 0.034). A highly significant association was observed between (i) tumour-associated expression of these two oncoproteins (P = 0.001) and (ii) COX-2 histoscore and the presence of Bcl-2 expression (P = 0.002). COX regression analysis demonstrated no significant relationship between (i) the presence or absence of either COX-2 or Bcl-2 and patient survival or (ii) COX-2 histoscore and patient survival. Conclusions:, COX-2 and Bcl-2 may promote phaeochromocytoma malignancy, and these oncoproteins may be valuable surrogate markers of an aggressive tumour phenotype. [source] Habitat heterogeneity influences connectivity in a spatially structured pest populationJOURNAL OF APPLIED ECOLOGY, Issue 2 2006G. S. HAMILTON Summary 1Patterns of connectivity influence pest population system dynamics, and it is essential to consider connectivity when planning effective management strategies. Traditional connectivity models often consider populations embedded in a matrix of unsuitable habitat. This approach is unlikely to be applicable to those pest species that can utilize most of the landscape in which they live. There is therefore a need for a simple and flexible tool to assess connectivity in such systems. 2In this study, we developed a new model in which contiguous resource patches that differ in quality, and landscape elements that impede dispersal, impact on connectivity within a population system. The model was applied to a wild rabbit population system, a well-studied pest species in Australia. An independent population genetic data set was used to validate the model. 3There was a highly significant association between pairwise population connectivity and the genetic data (Mantel test, r=,0·502, P= 0·002). As predicted, two populations that showed very low connectivity were strongly isolated genetically. These sites appeared to be substantially isolated because of forests, which acted to impede rabbit dispersal. When these sites were excluded from analysis, connectivity indices again explained the pattern of genetic data (Mantel test, r=,0·46, P= 0·037). This showed that both spatial variation in resource quality and forests influenced connectivity in this system. Sensitivity analyses confirmed that the distribution and extent of forests was important in limiting connectivity to some sites. The model was relatively robust to changes in population parameters. 4Synthesis and applications. Connectivity among wild rabbit populations in this system was strongly influenced by habitat heterogeneity, rather than factors such as geographical distance or major landscape elements such as rivers, both of which are traditionally considered to influence system dynamics. This may have substantial implications for many pest systems, and suggests that the impact of habitat heterogeneity on connectivity should be considered when planning efficient management strategies. [source] Osteoprotegerin Plasma Levels are Strongly Associated with Polymorphisms in Human Homologue of the Mouse Progressive Ankylosis (ANKH) GeneANNALS OF HUMAN GENETICS, Issue 3 2007Y. Vistoropsky Summary Osteoprotegerin inhibits osteoclastogenesis and plays an important role in the control of bone resorption. However, the genetic mechanisms underlying regulation of OPG levels are currently not fully elucidated. The aim of the present study was to determine whether the ANKH gene, which plays a central role in bone mineralization, contributes to the genetic regulation of OPG levels. A family-based association study used a sample of 159 ethnically homogeneous nuclear families, comprising 556 apparently healthy individuals. Statistical analyses included family aggregation analysis of OPG variation and four types of transmission disequilibrium tests. Each individual was genotyped for 11 SNPs in the ANKH gene. Four TDTs consistently showed a highly significant association between OPG levels and the intronic SNP rs875525 located between exons 6 and 7. The combined p-value for four tests to reject the null hypothesis of no association was 0.0003. Furthermore, haplotypes generated between rs875525 and two additional neighbouring SNPs (rs2291943 and rs2288474) also revealed a significant association with OPG plasma levels (p < 10,4 -10,3). ANKH genetic polymorphisms in the area between SNP rs2291943 and rs2288474 are strongly associated with OPG plasma levels. The molecular mechanism underlying this association is not obvious, and therefore these results should be regarded cautiously until they are confirmed in independent studies. [source] Strong associations between gene function and codon usageAPMIS, Issue 9 2003ANDERS FUGLSANG The association between codon usage and gene function was analyzed in the complete genomes of Eschericia coli, Bacillus subtilis, Lactococcus lactis and Campylobacter jejuni, using the functional annotation provided by NCBI. Two distinctly different ways of quantifying codon usage were used in the analysis. By using contingency tables it was found that for most amino acids a highly significant association with gene function exists for all species, indicating that codon usage at the level of individual amino acids is generally closely coordinated with gene function. By computing the effective number of codons in the annotated genes and comparing the median values in groups of different gene functions it was shown for all species that codon bias gene by gene also differs. [source] The autoimmune regulator gene (AIRE) is strongly associated with vitiligoBRITISH JOURNAL OF DERMATOLOGY, Issue 3 2008R. Tazi-Ahnini Summary Background, Vitiligo is an autoimmune disorder that occurs with greatly increased frequency in the rare recessive autoimmune polyendocrinopathy,candidiasis,ectodermal dystrophy syndrome (APECED) caused by mutations of the autoimmune regulator (AIRE) gene on chromosome 21q22·3. We have previously detected an association between alopecia areata and single nucleotide polymorphisms (SNPs) in the AIRE gene. Objectives, To report the findings of an extended study including haplotype analysis on six AIRE polymorphisms (AIRE C,103T, C4144G, T5238C, G6528A, T7215C and T11787C) in vitiligo, another APECED-associated disease. Methods, A case,control analysis was performed. Results, Results showed a strong association between AIRE 7215C and vitiligo [P = 1·36 × 10,5, odds ratio (OR) 3·12, 95% confidence interval (CI) 1·87,5·46]. We found no significant association with the other polymorphisms individually. However, haplotype analysis revealed that the AIRE haplotype CCTGCC showed a highly significant association with vitiligo (P = 4·14 × 10,4, OR 3·00, 95% CI 1·70,5·28). To select the most informative minimal haplotypes, we tagged the polymorphisms using SNP tag software. Using AIRE C,103T, G6528A, T7215C and T11787C as tag SNPs, the haplotype AIRE CGCC was associated with vitiligo (P = 0·003, OR 2·49, 95% CI 1·45,4·26). Conclusions, The link between vitiligo and AIRE raises the possibility that defective skin peripheral antigen selection in the thymus is involved in the changes that result in melanocyte destruction in this disorder. [source] | |||||||||||||