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Genetic causes of medullary thyroid carcinoma and Hirschsprung's disease
Václavíková, Eliška
Genetic causes of medullary thyroid carcinoma and Hirschsprung's disease Abstract Medullary thyroid carcinoma (MTC) and Hirschsprung's disease (HSCR) are classified as simple neurocristopathies, i.e. diseases linked to neural crest-derived cells. MTC is derived from parafollicular cells of the thyroid and HSCR is characterized by absence of enteric ganglia in the gastrointestinal tract. The RET proto-oncogene is only expressed in neural crest-derived cells, including parafollicular cells and enteric neurons. The RET encodes a transmembrane tyrosinekinase receptor that plays an important role during proliferation, differentiation and cell survival, and activates many signaling pathways. If the strictly regulated activation fails, e.g. due to mutations in the specific gene locations, the RET becomes a highly effective oncogene. Activating germline mutations in the RET proto- oncogene lead to hereditary forms of MTC, whereas sporadic forms of MTC are caused by somatic mutations in the tumor tissue. On the contrary, inactivating mutations induce migration failure of ganglion cell precursors during the development of enteric nervous system and result in the development of HSCR. In rare cases, the coexistence of both diseases is caused by mutations with a dual gain-of-function and loss-of-function character....
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Determination of mtDNA sequence variation in czech population for the usage in forensic genetics.
Řadová, Marie ; Coufalová, Pavla (advisor) ; Vaněk, Daniel (referee)
In forensic research and practice is used an analysis of nuclear DNA commonly. However, in some cases we can use only mitochondrial DNA. The mtDNA is maternally inherited and it is located in the each cell approximately in 500 copies. Barring mutation in special noncoding segments, the mtDNA sequence of siblings and all maternal relatives is identical. This unique haplotyp can be helpful in forensic cases, such as analyzing the remains of a missing person, where known maternal relatives can provide reference samples for direct comparison to the questioned mtDNA type. MtDNA is also very resistant to the external influences, so in the cases where the amount of extracted DNA is very small or degraded it is more likely that a DNA typing result can be obtained by typing mtDNA than by typing polymorphic markers found in nuclear DNA. If we want to have a certain probability to exclude or confirm the match of two samples, classify suspect or missing person into a population, we need some enough wide comparison by the population databases. Then we can study the frequencies of different haplotypes in particular population. The aim of this thesis is summery of history of DNA analysis, mtDNA sequencing and comparison of data available in published databases in the world and mainly in the Czech Republic. There is also...
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Genetická a morfologická variabilita skupiny \kur{Melampyrum nemorosum}
DRAHNÍK, Petr
Melampyrum nemorosum agg. is very complicated group of hemiparasitic plants. According to the traditional concept, 15 species is distinguished. Recent molecular analyses show a need of critical taxonomic revision of group and a potential importance of ancient hybridization. Analysis of 3 regions of cpDNA (trnTUGU-trnLUAA, psbA-trnHGUG, rpl32-trnLUAG) and 2 regions of nuclear DNA (Agt1 and At103) reveals well supported lineage with limited geographical distribution. Morphology and genome size of genetically supported lineages were compared.
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Genetická a morfologická variabilita skupiny \kur{Melampyrum nemorosum}
DRAHNÍK, Petr
Melampyrum nemorosum agg. is very complicated group of hemiparasitic plants. According to the traditional concept, 15 species is distinguished. Recent molecular analyses show a need of critical taxonomic revision of group and a potential importance of ancient hybridization. Analysis of 3 regions of cpDNA (trnTUGU-trnLUAA, psbA-trnHGUG, rpl32-trnLUAG) and 2 regions of nuclear DNA (Agt1 and At103) reveals well supported lineage with limited geographical distribution. Morphology and genome size of genetically supported lineages were compared.
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