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Karyotype differentiation of Euscorpius scorpions (Scorpiones: Euscorpiidae) in Europe
Novotný, Tomáš ; Šťáhlavský, František (advisor) ; Ráb, Petr (referee)
The aim of presented work is to provide characteristics of the karyotypes of scorpions of the genus Euscorpius. Genus Euscorpius is a typical representative of scorpions in Europe. Its occurrence is wide throughout Europe. Until now, 18 species of this genus have been described. In this work six species were karyologically analyzed and one species was shown to possess only basic diploid number of chromosomes: E. carpathicus - 2n=90, E. concinnus - 2n=88, E. hadzii - 2n=68, E. sicanus - 2n=66, E. tergestinus - 2n=60, E. naupliensis - 2n=60, E. italicus - 2n=36. Description of the karyotypes revealed that all species studied exhibit achiasmatic meiosis; no presence of sex chromosomes was detected. The basic hypothesis of phylogenetic relationships and karyotype evolution of the genus Euscorpius was outlined. High interspecies variability in chromosome total count was found and by analysis of the 16S rRNA gene the taxonomic status of the species was confirmed. Hence, it seems that cytogenetic methods can contribute to the understanding of species diversity and differentiation of possible cryptic species within the genus Euscorpius.
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Karyotype analysis of selected representatives of two pedipalpid orders, Amblypygi and Uropygi
Sember, Alexandr ; Král, Jiří (advisor) ; Ráb, Petr (referee)
Karyotype analysis of selected species from arachnid orders Amblypygi and Uropygi Whip spiders (Amblypygi) and whip scorpions (Uropygi) represent relict arachnid orders which has been found already at Upper Carboniferous strata. Although cytogenetic data from amblypygids and uropygids might be important to reconstruct karyotype evolution of arachnids, cytogenetics of these orders is almost unknown. Presented study is aimed in analysis of karyotype and meiosis in 16 species of Amblypygi and 4 species of Uropygi. Both groups are characterized by considerable range of diploid chromosome numbers (2n = 24 - 86 in Amblypygi and 36 - 66 in Uropygi). Analysed species does not exhibit morfologically differentiated sex chromosomes. Differentiation of sex chromosomes on molecular level was revealed in amblypygid Paraphrynus mexicanus by comparative genome hybridization. Obtained data indicate XY/XX sex chromosome system in this species. Comparison of karyotype data indicates reduction of chromosome numbers during evolution of both orders. In Amblypygi, this reduction was accompanied by increase of number of biarmed chromosomes. This trend is not apparent in Uropygi. Karyotypes of most analysed amblypygids and uropygids are also characterized by low amount of heterochromatin. Most studied species exhibit two pairs...
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Cytogenetics of bed bugs (Cimicidae) as a model representative of true bugs (Heteroptera)
Sadílek, David ; Johnson Pokorná, Martina (referee) ; Vilímová, Jitka (advisor)
Cytogenetics of bed bugs (Cimicidae) as a model true bugs (Insecta: Heteroptera) The thesis provides current opinions about a phylogeny of bed bugs, family Cimicidae, and their classification within the order Heteroptera. There are briefly summarized cytological data about the order Heteroptera, known karyotypes of the cimicid subfamilies and introduction to cytogenetics of species Cimex lectularius Linnaeus, 1758. Heteroptera species differ from other organisms by holokinetic chromosomes, a character, in which quite frequently take place chromosomal fragmentation and fusion. Several families posses smaller pair of m chromosomes, which behave during meiosis differently from the other chromosomes. Diploid chromosomal number is extremely variable, it ranges from four (family Belostomatidae) to 80 chromosomes (family Miridae). The behavior of chromosomes in the family Cimicidae is very specific. Sex-chromosomes univalents are connected by thread-like collochores and form so-called pseudobivalents during achiasmatic post-reductional meiosis. Rare polymorphism in a number of X chromosomes occurs in Cimex lectularius populations. The diploid karyotype always consists of 26 autosomal chromosomes and at least two but up to 15 X chromosomes and one Y chromosome. The number of X chromosomes can be variable...
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Digital image analysis of mitotic chromosomes
Hávová, Mariana ; Babula, Petr (referee) ; Škutková, Helena (advisor)
Changes in chromosome number and structure may cause serious diseases. Cytogenetic tests leadin to set of karyotype are done for detecting these abnormalities. Chromosomes are visualised with proper methods and karyotype is made up most often. Manual karyotyping is time-consuming and expensive task. Because of this, researchers have been developing automated karyotyping systems. Karyotyping systems classify chromosomes into classes based on their characteristic features. Overlapping and bent chromosomes are limitations for automatic classification since they ocur at almost every mitosis. Accuracy and reliability of karyotyping systems still depend on the human intervention. Overcoming of these problems and development of fully automated system is the aim of modern approaches.
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Examination of the karyotype from amniotic fluid
MOULEOVÁ, Pavlína
My bachelor work is focused on the examination of the karyotype from amniotic fluid. The examination of the karyotype from amniotic fluid being obtained by amniocentesis is a basic method of prenatal diagnostics. It is possible to confirm or exclude fetal chromosomal aberrations with this examination. Amniocentesis is an invasive method of obtaining amniotic fluid. The risk of complications associated with amniocentesis, such as a miscarriage or a premature rupture, is around 0.5-1%. The indication for amniocentesis is performed by a geneticist, mostly on the basis of positive results of screening examinations. Amniocentesis itself is done between the sixteenth and eighteenth week of pregnancy. The self cultivation and the following processing of the preparation is usually between 10-17 days, therefore it is very important to set a term for this amniocentesis. Cells are separated by centrofugation from amniotic fluid. After that these are seeded in a culture medium where they grow to the required amount. At the end of the cultivation period, the division of cells is blocked in the metaphase of mitotic division by adding Colcemid. This is followed by processing for the microscopic views which includes hypotonia, fixation and the creation of native preparations which are stained most frequently by Giemsa - Romanovsky technique for G-banding. The these samples are evaluated in the light microscope with using a computer karyotyping system. During the stage in the laboratory Genetics - Plzeň s.r.o., I took the measurements of 50 samples of amniotic fluid. Forty-eight samples of all these were negative ( it menas that they had a normal karyotype) and 2 samples were positive . One of them was trisomy of the 21st chromosome, which is characteristic of Down syndrome. The second one was the reciprocal translocations, which was determined by FISH.
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Molecular differentiation of sex chromosomes in ermine moths of genus \kur{ Yponomeuta}
VESELÁ, Jana
Structure of the karyotype of three species in ermine moths (Yponomeuta: Yponomeutidae, Lepidoptera) was investigated by means of several cytogenetic methods (DAPI staining, orcein staining, CGH and GISH with telomeric probe) focusing on their sex chromosomes. Additionally, the origin of the Z2 chromosome in the WZ1Z2/Z1Z1Z2Z2 sex chromosome system (specific for this family of butterflies) was tested using southern hybridization.
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The occurrence of chromosomal aberrations in the Czech Republic
LANDOVÁ, Ivana
The objektive of this bachelor's thesis was to describe the occurrence of chromosomal aberrations in the Czech Republic and to verify whether the literary data agree with the current occurrence rates. This thesis consist of 2 parts: The theoretical part of the thesis describe phenotypic symptoms and signs of chromosomal aberrations, their origin, causes and occurence rates in the population as reported in the literature. In the practical part, I tried to verify these occurrence rates of the aberrations based on results of investigations (both prenatal and postnatal) provided by the following laboratories: Genetika Plzeň s.r.o., Institute of Reproductive Medicine and Genetics, Karlovy Vary, and Institute of Medical Genetics, University Hospital, Pzeň. I have also used data obtained from the Czech Institute of Medical Information and Statistics (ÚZIS) as well as data found in various Internet sites. The purpose of this research was to provide graphics demonstrating the results, unify various types of results and try to find possible interrelations. It is obvious from the results that there has been a shift in the age group of maximum fertility from ages 20 ? 24 in 1995 to 30 ? 34 years in 2008. The mean age of mothers whose foetuses were diagnosed with Down syndrome in individual years ranged in the interval from 27 to 37.5 years. There were no differences in the representation of Down syndrome in individual years, and also the representations found in individual workplaces did not show any significant differences, ranging from 0.19 to 1.52%. The mean occurrence rate of Down syndrome as calculated from the results published by ÚZIS from the period 1994 ? 2007 was 1 for 1,700 live births. I succeeded in realizing all the targets of my work. Both prenatal and postnatal occurrence rates of aberrations in the workplaces of interest varied for individual years or showed only minor signs of increasing or decreasing rates. Monitoring of larger number of workplaces appears warranted to confirm my hypothesis.
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Optimization of cytogenetic techniques in a model aphid, \kur{Diuraphis noxia} (Aphididae)
VESELÁ, Jana
Several cytogenetical methods for investigation of karyotyp were used in an aphid species, Diuraphis noxia (Hemiptera: Aphididae). These methods (FISH with telomeric probe, FISH with rDNA probe, FISH with histone probe and silver staining) were optimized for application to a sister group Adelgidae, where they could be useful for better differentiation of species in particular stages of their complicated life cycle.
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