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Molecular-cytogenetic diagnostics of marker chromosomes
Tesner, Pavel ; Kočárek, Eduard (advisor) ; Zemanová, Zuzana (referee) ; Šubrt, Ivan (referee)
Supernumerary marker chromosomes (sSMCs) are a relatively rare cytogenetic phenomenon. Their laboratory examination is often difficult, and the clinical interpretation is even more challenging. The main reason is that most sSMC carriers have no clinical manifestations. The chromosome origin and exact range of the aberration are very important, as well as the fact that sSMCs are often found in mosaics that can strongly influence both the phenotype and the interpretation of result. Prenatal sSMC finding is one of the most challenging situations in both clinical and laboratory genetics. This work deals with the investigation process of sSMC carriers using molecular cytogenetic techniques, especially fluorescence in situ hybridization (FISH). We investigated a total of 67 families collected both prospectively and retrospectively, and we found 70 unique sSMCs in a total of 74 individuals. Six cases were familial and in three cases two sSMCs were found in one individual. According to the initial karyotype finding, the cases were divided into two groups, sSMCs supernumerary to a normal karyotype (group A) and sSMCT s supernumerary to the Turner karyotype (group B). The chromosomal origin was successfully determined in 88,6 % sSMCs. In group A the most common findings were sSMCs derived from chromosome 15,...
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Monitoring of children's cancer chemoresistance molecular cytogenetic methods
Procházka, Pavel ; Eckschlager, Tomáš (advisor) ; Kočárek, Eduard (referee) ; Kuglík, Petr (referee)
Souhrn Disertacni prace se zabyva chemorezistenci detskych nadorovych onemocneni adetekci cytogenetickych zmen, ktere s ni souvisi. Ovlivneni rizikovych forem detskych nadoru vyzaduje pouziti vysokych davek chemoterapie, ktera muze vest ke vzniku chemorezistence. Prukaz chromozomalnich aberaci muze prispet k urceni prognozy apredikce efektu lecbychemorezistentnichnadoru. Vetsinu vysledku jsme ziskalistudiem neuroblastomu (NBL). Ostatni prezentovane vysledky pak predstavuji geneticke zmeny u Ewingova sarkomu a u detskych feochromocytomu. Ke studiu chromozomalnichaberaci bylypouzitymetodykomparativni genomova hybridizace (CGH)a array CGH doplnene o vysetreni mnohobarevnou nebo int fzni fuor c brdi nst. Zmenyv expr naur mRNA byl s rera l escen ni hy i zaci i iu esi ovni yvyeteny expresni cipovou analyzou doplnenou o kvantitativni polymerazovou retezovou reakci, zmeny v expresiproteinu bylyvysetrenypomoci westernblottingu nebo prutokovou cytometrii. Predkladana disertace je komentovany soubor sesti publikaci. Studium chromozomalnich aberaci Ewingovych sarkomu predstavuje literarni resersi doplnenou o vlastni vysledky. Prace tykajici se feochromocytomu je jednim z nejvetsich souboru podrobnegeneticky vysetrenych detskych feochromocytomu. Nejobsahlejsi castse zabyva cytogenetickymizmenamiu NBL. Dlouhodobou...
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Molecular cytogenetic analysis of mosaic chromosomal abnormalities
Cinkajzlová, Anna ; Kočárek, Eduard (advisor) ; Král, Jiří (referee)
The focus of this diploma thesis is on mosaic numerical and structural chromosomal aberrations. In its theoretical part, general problems of mosaicism, its phenotypic effect, mechanisms of origin, related epigenetic modifications, and diagnostic options are described. The methodical part of the thesis then primarily refers to fluorescence in situ hybridization (FISH) and its application in the diagnostics of mosaicism. This method was used in the examination of 29 patients with numerical as well as structural abnormalities of autosomes or gonosomes with proven or suspected mosaicism. On the basis of this analysis, possible errors of measurement were determined and data for statistic evaluation were retrieved. For the examinations of three patients an alternative of the comparative genomic hybridization, the array CGH technique, was applied. The FISH method, although being based on random selection and human factor, proved sufficient sensitivity as well as specificity in the field of low-frequency mosaicism diagnostics. The main critical factors responsible for potential misinterpretation of the data arose from inherent characteristics of the biological material, incorrect targeting of the analysis, probe instability, bleed through effect and absence of mitosis during the structural aberrations analysis.
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Possibilities of assessment and the relevance of the results of FISH analysis of chromosomal abnormalities in mosaics
Neužilová, Linda ; Kočárek, Eduard (advisor) ; Panczak, Aleš (referee)
This bachelor thesis deals with mosaicism and its detection. Mosaicism is defined as the presence of two or more cell lines with different karyotype in the patient's body. An aspect of particular importance for the resulting phenotype is the overall ratio in which the individual cell lines are represented. It is often found in Turner and Klinefelter syndrome. Turner syndrome is caused by the loss of a part of, or the whole of the X chromosome in females and it belongs among the most common chromosomal constitutions, found in spontaneous abortions. However, it is estimated that only about half of the women with Turner syndrome have karyotype 45,X; the others are mosaics or have other abnormalities of the chromosome X. The main aim of the practical part of this thesis was to evaluate the possibilities of detecting mosaicism using fluorescence in situ hybridization (FISH) and to consider the possible factors affecting the accuracy of the examination. The objectives of the assessment were the individual variability between the evaluators and also the differences caused by using two differently labelled probes. As a result, the thesis confirms that the FISH method enhances the accuracy of the results of conventional cytogenetic examination and it is suitable for analysis of mosaicism thanks to the possibility of...
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Molecular cytogenetic analysis of cryptic chromosomal rearrangements
Kindlová, Markéta ; Kočárek, Eduard (advisor) ; Musilová, Jana (referee)
Microdeletion syndromes occur in high incidence in the population, the most common syndrome is DiGeorge syndrome. Its incidence is 1 : 4 000. Another relatively frequent syndromes are Williams-Beuren syndrome, Miller-Dieker syndrome, 1p36 deletion syndrome and others. Most of these syndromes cause the serious clinical disorder to their carriers. Early and reliable diagnosis can help in treatment of the affected patient (education, surgical correction, physiotherapy, pharmacotherapy) or in prenatal diagnostics. We use FISH (fluorescent in situ hybridization) or PCR (polymerase chain reaction) based methods to analyse cryptic chromosomal rearrangements, which cause these syndromes.
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Molecular cytogenetic analysis of marker chromosomes and related abnormalities
Semanko, Adam ; Kočárek, Eduard (advisor) ; Holá, Dana (referee)
The primary focus of this diploma thesis is on marker chromosomes and phenotypically similar human karyotype polymorphisms, variants of short acrocentric arms in particular. The first half provides a very useful review of literature concerning different aspects of both sSMC and human polymorphisms such as their origin, inheritance, associated phenotype, formation and molecular cytogenetic methods that are applied in the process of identification of these aberrations. The methodical emphasis is on FISH and its modifications (e.g. M-FISH, acro M FISH, cen M-FISH) as well as on the CGH methods. The main objective was to test the above-mentioned methods and state their limitations and applications. Thus, in the other half we provide evaluations of commonly used methods and introduce new strategies that could be implemented to make the identification of these additional chromosomes or satellite translocations more effective. All the conclusions are based on the analysis of 7 patients with sSMC and 4 patients with variants involving acrocentric NOR regions. The results of our thorough research into their karyotypes have been compared with similar findings in the literature. Last but not least, we tried to establish a link between observed abnormalities and the type of a chromosomal aberration at hand.
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