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Genetic Origins (genetic + origins)
Selected AbstractsGenetic origins and clinical phenotype of familial and acquired erythrocytosis and thrombocytosis,AMERICAN JOURNAL OF HEMATOLOGY, Issue 1 2009Melanie J. Percy Familial and acquired erythrocytosis and thrombocytosis are characterized by myeloid lineage hyperproliferation, which is either single or multi-lineage in origin. The single lineage disorders exhibit Mendelian inheritance with polyclonal hematopoiesis and often arise from a single genetic defect. In contrast, the multi-lineage disorders exhibit complex patterns of inheritance with multi-genetic origins and clonal hematopoiesis. They have the potential to acquire JAK2 somatic mutations, but this is not the primary event. Identification of the disease-causing genes will enable better classification of familial and acquired erythrocytosis and thrombocytosis. Furthermore, it will provide an insight into the mechanisms regulating myeloid cell proliferation. Am. J. Hematol., 2009. © 2008 Wiley-Liss, Inc. [source] Quantitative FISH analysis on interphase nuclei may improve diagnosis of DNA diploid breast cancersDIAGNOSTIC CYTOPATHOLOGY, Issue 4 2002Khuong Truong Abstract The detection of DNA aneuploid cells using flow cytometry is an indication for the presence of tumor cells, but when DNA diploid cells are found in 25,33% of the cases, the diagnostic and prognostic significance of DNA ploidy is more limited. We analyzed interphase nuclei after in situ hybridization and using image cytometry on 50 breast tumors with diploid DNA content to investigate whether early chromosome rearrangements were detectable and if their occurrence was clinically significant. Imbalances between the two arms of chromosome 1 were found in 55% of the cases and values ranged from 1.5,3.0. Comparison with histological data showed that Grade I tumors mainly have imbalances (67%) and that Grade III tumors were mainly without the imbalance (67%), whereas Grade II tumors were intermediate (50% imbalance). These data suggest that the diagnosis of DNA diploid cases may be improved by using interphase FISH. In addition, the data also indicates that early breast tumors may have different genetic origins, which is important in the comprehension of tumor malignancy in early stages, especially for preinvasive lesions. Diagn. Cytopathol. 2002;26:213,216. © 2002 Wiley-Liss, Inc. [source] Isolation and characterization of highly polymorphic microsatellites in tea (Camellia sinensis)MOLECULAR ECOLOGY RESOURCES, Issue 3 2004SUSAN FREEMAN Abstract Relatively little is known about the diversity and origins of tea. The highest value tea products are sold on the basis of their region of origin but there are currently no methods available to verify the claims made on packages. We have developed 15 microsatellite loci for tea. These have been evaluated for polymorphism in a set of tea clones to determine their usefulness for authentication purposes. The majority of the microsatellites developed proved to be highly polymorphic both between and within different geographical origins and offer the potential to investigate the population genetics and genetic origins of tea. [source] The origin and evolution of human pathogensMOLECULAR MICROBIOLOGY, Issue 1 2005Eduardo A. Groisman Summary What are the genetic origins of human pathogens? An international group of scientists discussed this topic at a workshop that took place in late October 2004 in Baeza (Spain). Focusing primarily on bacterial pathogens, they examined the role that pathogenicity islands and bacteriophages play on determining the virulence properties that distinguish closely related members of a given species, such as host range and tissue specificity. They also discussed an instance in which closely related bacterial species differ in the production of a cell surface modification mediating resistance to an antibiotic as a result of the disparate regulation of homologous genes. In certain pathogens, genes normally carrying out housekeeping functions may adopt new functions, whereas in other organisms, genes that respond to stresses associated with non-host environments are silenced during infection to prevent the expression of products that interfere with the normal colonization process. The adaptive behaviour of certain pathogens relies on gene variation at certain loci that by virtue of containing polymeric repeats in regulatory or coding regions, can generate variants that may or may not express products that modify the cell surface of the organism. The meeting also addressed the properties of ORFan genes, which have no homologues in the sequence databases, as well as the creation of genes de novo by duplication and divergence. [source] Genetic diversity among populations and breeding lines from recurrent selection in Brassica napus as revealed by RAPD markersPLANT BREEDING, Issue 1 2004M. Yuan Abstract Recurrent selection facilitated by dominant male sterility has been conducted to broaden the genetic basis for cultivar development in Brassica napus. This study aimed to evaluate the genetic variation in four base populations (C0-C3) and breeding lines from two of the populations produced during recurrent selection by random amplified polymorphic DNA (Rapd) markers. Genetic variation in four populations declined gradually with the advance of selection cycles as measured by expected genetic heterozygosity (from 0.2058 in C0 to 0.1536 in C3) but the decline was not statistically significant. When compared with the average genetic distances for 21 germplasm collections with wide geographical and genetic origins (0.4712) and seven breeding lines from pedigree selection (0.2059), seven breeding lines selected from the C1 population and 11 from the C3 population had a larger average genetic distance (0.5339 and 0.5486, respectively). Clustering analysis indicated that the lines from recurrent selection had a much lower genetic similarity than lines from pedigree selection. Our results suggest that base populations derived from recurrent selection could provide a wider genetic variation for selection of breeding lines with more broad genetic bases. [source] Genetic and environmental influences on frontal EEG asymmetry and alpha power in 9,10-year-old twinsPSYCHOPHYSIOLOGY, Issue 4 2009Yu Gao Abstract Modest genetic influences on frontal EEG asymmetry have been found in adults, but little is known about its genetic origins in children. Resting frontal asymmetry and alpha power were examined in 951 9,10-year-old twins. Results showed that in both males and females: (1) a modest but significant amount of variance in frontal asymmetry was accounted for by genetic factors (11,28%) with the remainder accounted for by non-shared environmental influences, and (2) alpha power were highly heritable, with 71,85% of the variance accounted for by genetic factors. Results suggest that the genetic architecture of frontal asymmetry and alpha power in late childhood are similar to that in adulthood and that the high non-shared environmental influences on frontal asymmetry may reflect environmentally influenced individual differences in the maturation of frontal cortex as well as state-dependent influences on specific measurements. [source] Sharing genetic origins information in third party assisted conception: a case for Victorian family values?CHILDREN & SOCIETY, Issue 1 2000Eric Blyth In the United Kingdom (UK) approximately 2500 children are born each year as a result of third party assisted conception. Since formal record keeping by the statutory regulatory body, the Human Fertilisation and Embryology Authority, began in 1991, the total number of children known to have been born from all forms of third party assisted conception exceeds 13 500. Although the records contain information about these children's genetic origins, including the identity of the donor, current legislation severely circumscribes their ability to access this information and, save in very exceptional circumstances, they are not permitted to learn the identity of the donor. Consequently, they are the only individuals in the UK whose inability to learn the identity of both their genetic parents is formally endorsed by statute. This paper identifies different approaches to exchanging genetic origins information in third party assisted conception. It provides a critique of the model currently in force in the UK and advocates its replacement by a system that more closely resembles that introduced in Victoria (Australia) in 1998. Copyright © 2000 John Wiley & Sons, Ltd. [source] A severe form of Noonan syndrome and autosomal dominant café-au-lait spots , evidence for different genetic originsACTA PAEDIATRICA, Issue 4 2009Anna-Maja Nyström Abstract Aim: The clinical overlap among Noonan syndrome (NS), cardio-facio-cutaneous (CFC), LEOPARD and Costello syndromes as well as Neurofibromatosis type 1 is extensive, which complicates the process of diagnosis. Further genotype,phenotype correlations are required to facilitate future diagnosis of these patients. Therefore, investigations of the genetic cause of a severe phenotype in a patient with NS and the presence of multiple café-au-lait spots (CAL) spots in the patient and four members of the family were performed. Methods: Mutation analyses of candidate genes, PTPN11, NF1, SPRED1 and SPRED2, associated with these syndromes, were conducted using DNA sequencing. Results: A previously identified de novo mutation, PTPN11 F285L and an inherited NF1 R1809C substitution in the index patient were found. However, neither PTPN11 F285L, NF1 R1809C, SPRED1 nor SPRED2 segregated with CAL spots in the family. The results indicate that the familial CAL spots trait in this family is caused by a mutation in another gene, distinct from previous genes associated with CAL spots in these syndromes. Conclusion: We suggest that the atypical severe symptoms in the index patient may be caused by an additive effect on the F285L mutation in PTPN11 by another mutation, for example the NF1 R1809C or alternatively, the not yet identified gene mutation associated with CAL spots in this family. [source] | |||||||||||||