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Utilisation of molecular cytogenetic techniques in productive genetics
Paulasová, Petra ; Macek, Milan (advisor) ; Korabečná, Marie (referee) ; Vodička, Radek (referee)
Title.: Utilisation of molecular cytogenetic techniques in reproductive genetics Chromosomal abnormalities constitute one of the most important causes of birth defects, fertilization failure and/or human infertility. Approximately, 40-50% of human conceptuses are chromosomally abnormal, 6% of the abortions during the first trimester of gestation are directly linked to chromosomal abnormality, while at term 0.6% of livebirths present with such features. Most of these abnormalities originate from the gametogenesis and arise through disturbed meiotic processes. Each gamete is a final and original product of the meiosis carrying a unique chromosomal set. Therefore, cytogenetic examination of individual gametes represents an important scientific challenge for our undrstandidng of the formation, incidence and etiology of aforementioned chromosomal abnormalities. Nonetheless, it is very technically demanding to perform efficient chromosomal investigation on gametes, hence single cells. My Ph.D. thesis is focused on the development of new techniques for the detection of chromosomal abnormalities in gametes and embryos. We developed a PNA-based technique as an alternative to conventional FISH and PRINS-based methods for fast, efficient and robust in situ detection of chromosomal abnormalities in human...
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A study of aneuploidy in gametes and embryos
Diblík, Jan ; Macek, Milan (advisor) ; Forejt, Julius (referee) ; Rubeš, Jiří (referee)
The thesis deals with improvement and clinical application of molecular cytogenetic methods for reproductive genetics. These methods include both clinical investigations used for improvement of diagnostic and therapeutic care for infertile couples and experimental methods that can become the basis of new diagnostic tools. The thesis concentrates on the study of aneuploidies, because they constitute a major complication of human reproduction especially by means of assisted reproductive technologies. Aims The main practical aim was the introduction of fluorescence in situ hybridization (FISH) for evaluation of chromosomes in sperm, polar bodies and blastomeres for prefertilisation and preimplantation diagnosis of aneuploidies. The main scientific objective was the study of chromosome localization in nuclei of blastomeres, that are removed from human embryos for preimplantation diagnosis. The aim of this study was to find, whether the localization of chromosomes in relation to the nuclear center and periphery is ruled by the same rules as in other cell types in later stages of development and whether the localization is influenced by aneuploidy. Next aim was to search for peripheral localization of chromosome X in embryos with more than one copies of the chromosome X. This could be a manifestation of X...
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Molecular syndromology: molecular genetic causes of rare diseases illustrated with Kabuki and Kabuki-like syndromes
Paděrová, Jana ; Macek, Milan (advisor) ; Baxová, Alice (referee) ; Fajkusová, Lenka (referee)
Kabuki syndrome (KS) is a dominantly inherited rare disease caused mainly by de novo pathogenic variants (henceforward mutations) in the KMT2D (formerly MLL2) and KDM6A genes. It is rare multisystemic syndrome characterized by intellectual disability (ID) and typical facial dysmorphism. KS is clinically heterogeneous, which complicates its clinical diagnosis. The first aim of this thesis was to introduce mutation testing of the two known KS causative genes in KS by Sanger DNA sequencing and by MLPA (Multiple Ligation Probe Amplification) at the Department of Biology and Medical Genetics of 2nd Medical Faculty of Charles University and University Hospital Motol, Prague followed by identification of underlying genetic mutations in KMT2D/KDM6A genes in 43 patients with phenotype typical for KS, who were indicated for this molecular genetic analysis by several collaborating genetic departments in the Czech Republic. We aimed to confirm or disprove of patient's clinical diagnosis, establish spectra of KMT2D/KDM6A mutations in the Czech population, render phenotype-genotype correlations and evaluate the phenotypic "MLL2-score" (published by Makrithanasis et al., 2013) utility as prediction tool for selection of cases for KMT2D sequencing. Mutations in the KMT2D gene were detected by Sanger DNA sequencing...
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Utilization of new generation sequencing methods to elucidate cystic fibrosis-like phenotype at patients with unclear illness of molecular type.
Matějčková, Iva ; Macek, Milan (advisor) ; Holá, Dana (referee)
Cystic fibrosis (CF) is genetically conditioned, autosomal recessive disease that occurs in the European population with a prevalence of about 1:2500 - 1:1800. In this disease we observe a mutation of the CTFR gene with subsequent fault in chloride channels. Such afflicted individuals usually suffer from chronic respiratory problems, pancreatic insufficiency, high concentration of chloride ions in sweat and obstructive azoospermia. Genetic testing of CFTR gene is indicated in individuals who meet the CF clinical picture and a positive sweat test (increased concentration of chlorides in the sweat). Genetic testing of the CFTR gene is usually done by using commercial kits detecting the most common mutations of the CFTR gene in the Czech Republic. If the testing results are negative, it is further performed an MLPA method that captures the larger deletions and duplications of gene, eventually a sequencing of all exons is. Despite the well-established algorithm of the testing, some patients suffering from symptoms of CF are left without genetic findings. Thanks to development of next generation sequencing, it is possible to make the diagnosis of CF more effective and uncover the variants that were not captured by previous methods.
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Molecular analysis in cases of inherited diseas
Mrázová, Lenka ; Kmoch, Stanislav (advisor) ; Jirsa, Milan (referee) ; Macek, Milan (referee)
Urcení vztahu mezi onemocnením a jeho molekulární podstatou je jedním z hlavních cílu lékarské genetiky. V rámci studie: "Molekulární analýza vybraných dedicne podmínených onemocnení" byly popsány postupy, které vedou k objasnení molekulární podstaty u onemocnení s již známými odpovednými geny i u onemocnení, u kterého byl odpovedný gen teprve identifikován. Studie prispela k rozšírení znalostí zkoumaných dedicných onemocnení. Zavedené postupy molekulárních analýz jsou soucástí diagnostiky na Ústavu dedicných metabolických poruch v Praze. Výsledky techto analýz slouží k prevenci, prognóze i lécbe onemocnení a u postižených rodin byla umožnena prenatální diagnostika. Výsledky byly publikovány v nekolika domácích i zahranicních odborných casopisech a prezentovány na mezinárodních konferencích. Nekteré z publikací byly dále citovány.
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Genetic factors in aetiology and phatogenesisof low gamma-glutamyltransferase cholestasis and hereditary jaundice
Cebecauerová, Dita ; Jirsa, Milan (advisor) ; Brdička, Radim (referee) ; Macek, Milan (referee)
(English) Recent progress in understanding the molecular mechanism of hepatobiliary disorders enabled the improvement of diagnostic accuracy and promoted the study of the regulation of gene expression and its potential modifying factors. Current achievement in the field of genetically determined cholestatic disorders is well illustrated in this thesis, focused on low gamma-glutamyltransferase (γGT) cholestasis and hereditary jaundice. The study describes several distinct defects of hepatocyte transport system, characterises underlying mutations and their phenotypic consequences and, finally, extends these studies for detailed characterisation of ATP8B1 gene regulatory regions. Chapters related to low γGT cholestasis - characterise rare type of mutation associated with benign course of PFIC type I (formerly BRIC1) and explain the putative mechanisms of mutation origin. - provide extensive study of severe forms of ABCB11 deficiency (PFIC2) including genotype-phenotype correlations in 109 affected families, evaluation of the specific ABCB11 genotypes' impact on BSEP immunostaining and risk of hepatobiliary malignancy. - identify and characterise yet unknown regulatory regions of ATP8B1, a gene mutated in Progressive Familial Intrahepatic Cholestasis type I. The studies demonstrate the complex structure...
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The increased diagnostic efficiency of QF-PCR for aneuploidy of amniotic fluid
Sedláková, Zdeňka ; Macek, Milan (advisor) ; Šolc, Roman (referee)
Quantitative fluorescence polymerase chain reaction (QF-PCR) is a molecular genetic method based on the amplification of microsatellites (Short tandem repeats, STR) and measurement of the peak heights of amplicons in the electropherogram. Currently, the QF- PCR deemed reliable, fast, and inexpensive method that is gradually replacing conventional cytogenetic analysis of aneuploidy (examination of long-term cultures of amniotic fluid). However, in certain cases it is impossible to determine the parental origin and meiotic aneuploidy by QF-PCR. The aim of this work was to verify the new dinucleotide STR markers on chromosomes 13, 16, 18, 21, and 22 and further increase the diagnostic efficiency of QF-PCR retaining other STR markers on chromosome 15, 16, 22 and to determine the population and the analytical characteristics of these markers. For all dinucleotide STR markers stutter occurred in high frequency and therefore there were found not to be suitable for routine diagnostics. STR markers for chromosomes 15, 16 and 22 were tested on 100 patients. We selected four informative markers for both chromosome 16 and 22, and three markers for chromosome 15. Thus, I expanded set of diagnostic STR markers in this thesis. Key words: QF-PCR, STR markers, prenatal diagnosis, trisomy.
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Study of genetic factors modifying the risk of onset and progression of colorectal and pancreatic cancer
Mohelníková Duchoňová, Beatrice ; Souček, Pavel (advisor) ; Skálová, Lenka (referee) ; Macek, Milan (referee)
Introduction: The aim of this study was to evaluate the role of genetic and lifestyle factors in the risk of onset and progression of colorectal and pancreatic cancer. The first part deals with the etiological factors and the importance of polymorphisms in biotransformation enzymes and genetic alterations in the gene CHEK2 in the origin of these malignancies. In the second part, the ABC transporter genes were analyzed as potential prognostic and predictive markers of a treatment's outcome. Materials and methods: The polymorphisms and other genetic alterations were detected using real-time PCR, allelespecific PCR and PCR-RFLP methods in DNA which was extracted from the blood of patients. The frequency of polymorphisms was evaluated and their importance was assessed with regard to the available epidemiological data. Gene expressions were determined by qPCR in paired samples of tumor tissue and adjacent non-tumorous parenchyma. Results: A majority of the observed polymorphisms failed to show a relationship between their presence and the risk of any of these malignancies. CYP2A13 variant allele*7 coding inactive enzyme was found in 7 of 265 controls and in none of 235 pancreatic carcinoma patients. In contrast, GSTP1-codon 105 Val variant allele and GSTT1-null genotype were associated with an elevated...
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Detection of minimal residual disease in bone marrow an peripheral blood in patients with breast cancer.
Čabiňaková, Michaela ; Tesařová, Petra (advisor) ; Konopásek, Bohuslav (referee) ; Macek, Milan (referee)
Introduction: Simultaneous detection of disseminated tumor cells (DTCs) and circulating tumor cells (CTCs) was shown to be associated with an especially poor prognosis and increased incidence of disease-related deaths in non-metastatic breast cancer patients. We analyzed the occurance of DTCs in bone marrow and CTCs in peripheral blood in patients with primary breast cancer, we evaluated the correlation of their presence with other prognostic markers and we investigated the changes in DTCs/CTCs number at different time points during treatment. Materials and methods: Blood of 50 patients with primary breast cancer were used for immunomagnetic separation and detection of circulating tumor cells using the commercial available system the AdnaTest Breast Cancer™ (AdnaGen GmbH, Langenhagen, Germany). Bone marrow aspirates from 50 patients were analyzed for DTCs by immunocytochemistry using the pancytokeratin antibody conjugated with FITC (Monoclonal Anti-Cytokeratin antibody F3418, Sigma Aldrich, USA). Results: DTCs were identified in 30% (15/50) and CTCs in 22% (11/50) of patients. We found that DTC positivity could point to a significantly high risk of larger primary tumor size (p- value 0.011) and significantly higher risk of lymph node involvement (p- value 0.002). For CTC positivity, no such...
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Molecular genetic and biochemical studies of selected inherited metabolic disorders, development and applications of new methods
Mušálková, Dita ; Hřebíček, Martin (advisor) ; Adam, Tomáš (referee) ; Macek, Milan (referee)
Inherited metabolic disorders (IMD) form a diverse group of several hundred different diseases with a relatively high cumulative incidence (stated up to 1:600). They are associated with accumulation of the substrates and lack of the products in specific metabolic pathways, which is caused by deficiency of the enzyme or its activator, or dysfunction of the transport protein. However, the underlying cause is at the DNA level. The grounds for different phenotype manifestation in patients with the same genotype are often not known. During my work at the Institute of Inherited Metabolic Disorders, I designed several new methods for the research of IMD and applied them in the patients and their families. I created procedures for the isolation of lysosomal membranes that are used for the research of lysosomal storage disorders and general properties of lysosomes. Next, I introduced several novel assays for determination of the X-inactivation ratio, which led to a significant increase of informative women. Nowadays, we use these methods in heterozygous women with X-linked diseases in order to study the influence of X-inactivation on the manifestation of the diseases. The cases of a girl with mucopolysaccharidosis type II, a girl with OTC deficiency and a family with the mutation in HPRT1 gene are described...
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