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Sequence diversity of mtDNA and genetic structure of eastern part of the African Sahel
Tlačbabová, Klára ; Černý, Viktor (advisor) ; Munclinger, Pavel (referee)
Eastern part of the African Sahel, connecting sub-Saharan Africa with North and East Africa, play an important role as a bidirectional corridor for vertically and horizontally migrations of populations. It is the strategic region to study human genetic diversity due to the presence of ethnically, linguistically, culturally and geographically diversity. This work is focused on the analysis of HVS-I and HVS-II segments of mtDNA. The work provides new information about genetic structure and migration activity of this region by analysis twelve populations belonging to three African linguistic families and different subsistent strategies. Analysis of mtDNA revealed the higher diversity of the populations of east Sudan and Horn of Africa, which is connected with the spreading of populations along the Nile River. It seems, that in this region linguistic factors have bigger impact on genetic diversity then the geografic ones. The opposite situation is observed in populations of Chad, where populations with similiar geografic location and different linguistic affilation revealed low genetic differentiation. The intra-population analysis shows the significant influence of genetic drift on the pastoralists living on the Red Sea Coast - Beja and Rashaida. In Beja is probably due to decrease of size of...
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Mosquitoes as hosts and vectors of protozoa transmitted to birds
Fialová, Magdaléna ; Svobodová, Milena (advisor) ; Munclinger, Pavel (referee)
Mosquitoes belong to significant representatives of inscet which are particularly studied due to their ability to transmit pathogens (viruses, bacteria, protozoa, worms) in many cases causing serious illnesses. The hosts of these pathogens can be various animals including birds. In this study I have focused on protozoa (especially Plasmodium and Trypanosoma) transmitted by a mosquito. Concerning trypanosomes the mosquito is one of several possible vectors and up to now there have been named two trypanosomes transmitted by birds, namely Trypanosoma culicavium and Trypanosoma thomasbancrofti. In the case of the genus Plasmodium the mosquito is the only vector and there are many more species of the genus Plasmodium, which mosquito transmits between birds. Key words: vector, mosquito, host, bird, Trypanosoma, Plasmodium, infection
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The impact of geography and subsistence on distribution of NRY haplogroups in Europe and Africa
Nováčková, Jana ; Černý, Viktor (advisor) ; Munclinger, Pavel (referee) ; Macholán, Miloš (referee)
Y chromosome is due to its special characteristics the ideal tool of archaeogenetic studies. Its diversity is influenced by several factors and I analysed two of them (geographical location and subsistence). I generated SNPs and STRs data from several loci of samples from Slovakia (156 samples, 5 regions) and sub-Saharan Africa, where I analysed samples of sedentary farmers (481 samples, 18 regions) and nomadic pastorals (405 samples, 16 regions). Slovakia is situated at the meeting point of two migration ways. First of them was spread from the east to the west and is associated with enlargement of haplogroup R1a in Europe. The second came from the Iberian Peninsula eastward and is associated with enlargement of haplogroup R1b. Results of MDS graphs replicate the geographical map of Europe. Slovakia is situated in the middle of Russian, Balkanian and Iberian samples. Correlation between genetics and geographic distances is indicated by hierarchical AMOVA analysis and Mantel tests. Populations in sub-Saharan Africa differ from each other by the subsistence pattern. Different life style influence the diversity of the Y chromosome. Nomadic pastoralists and sedentary farmers share different haplogroups, for example, while haplogroup R1b was detected only in nomadic pastoral groups, sedentary farmers...
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Whole-genome analysis of the house mouse hybrid zone
Janoušek, Václav ; Munclinger, Pavel (advisor) ; Choleva, Lukáš (referee) ; Chan, Yingguang Frank (referee)
Hybrid zones provide a valuable opportunity to study the process of speciation in real time. Untested combinations of genes from diverging populations come to the contact here causing a breakdown of genetic interactions and giving rise to reproductive isolation. Two house mouse subspecies (Mus musculus musculus/Mus musculus domesticus) form a narrow zone of secondary contact across Central Europe which is thought to be maintained by a balance between selection against unfit hybrids and dispersion of individuals. During my PhD study my collaborators and I used an array of ~ 1400 SNP markers to study patterns of introgression on a genome-wide scale across two/three house mouse hybrid zone transects. Our aim was to identify the genomic regions putatively harboring genes which are involved in the reproductive isolation between the two subspecies, characterize their distribution in mouse genome and assess genomic features associated with them. We were able to confirm on a genome-wide scale the importance of the X chromosome in the evolution of reproductive isolation. This chromosome exhibited introgression corresponding to strong negative epistasis and the patterns were consistent between transects pointing out to a common basis of reproductive isolation playing a role in two transects. Contrary to the...
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Cospeciation of bird ectoparasites
Gajdošová, Magdalena ; Munclinger, Pavel (advisor) ; Votýpka, Jan (referee)
In a case when two taxa are ecologically very closely related, speciation in one of them may induce speciation in the other one. This phenomenon is called cospeciation. Host specific parasites and their hosts are one of the systems where cospeciation has been frequently studied. Birds and their ectoparasites traditionally serve as a model system. Up to now dozens of cospeciation studies have been done on birds and their ectoparasites by comparing their phylogenetic trees. This work reviews the results of these studies and evaluates the possible effect of ecological and other factors. Cospeciation appears to take place often among birds and their permanent ectoparasites. 64% of the performed studies showed significant cospeciation. The rate of cospeciation varies greatly between different taxa. Some ecological aspects seem to play prominent role, especially those that provide dispersal opportunities to parasites.
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Avian malaria in the Swallow
Krausová, Simona ; Munclinger, Pavel (advisor) ; Votýpka, Jan (referee)
Long-distance migratory birds can encounter a wide range of parasites. Various populations of birds within one species use different migration routes and can also winter in different places. It can be supposed that birds which use different migration routes should be infected with different parasites. To study the relationship between the migration and the distribution of parasites we chose the worldwide species barn swallow (Hirundo rustica) and the avian malaria parasites. Swallows migrate long distances in different migrating routes. Some populations of swallows do not migrate, they are resident. This is the reason why swallow is a good model species for finding the answers to questions whether the populations using different migration routes are infected with different parasites or not and whether or not the diversity of parasites is wider in populations which migrate long distances in comparison with the resident populations. The malaria lineages of the genus Plasmodium and Haemoproteus were detected using nested PCR and sequencing. 1242 samples from 8 different localities from the USA, Europe and Asia were tested. We detected 24 different malaria lineages. Within the genus Plasmodium 4 of 16 lines were detected for the first time and in the genus Haemoproteus 3 of 6 lines were detected for the first...
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Altitude as factor influencing genetic structure of populations
Havelková, Markéta ; Munclinger, Pavel (advisor) ; Sedláček, Ondřej (referee)
Altitudinal gradient creates favorable system for research of populations from different altitudes and the influence of both neutral evolutionary processes and local conditions on their genetic structure. Adaptation of different genotypes to the local conditions is generally attributed to clinal variability of genetically determined features and geographic variation of phenotypes in populations. Thanks to their different adaptations to specific environments, genetic drift and possibly limited gene flow, populations can show significant variability that may lead to speciation events. Altitude represents selective pressure for organisms primarily due to reduced partial oxygen pressure, lowered temperature and increased exposure to UV light. Genetic differences created due to location of the population on altitude gradient can be evaluated based on the nature of climate change. There is strong evidence for the importance of altitude adaptations at molecular level for certain key genes, particularly for hemoglobin and mitochondrial genes.
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Mitochondrial DNA variability in the Central European populations.
Veselá, Monika ; Černý, Viktor (advisor) ; Munclinger, Pavel (referee)
The aim of this thesis was to evaluate the genetic diversity of mtDNA of populations in Central Europe and to assess its relation to geographic distances and/or linguistic affiliation of individual populations. For this purpose, HVS-1 mtDNA segments of 194 individuals of 6 Slovak populations were sequenced. Basic parameters of genetic diversity were estimated for obtained sequences, and compared with similar data published by other authors (4 798 sequences of HVS-1 mtDNA segment of 42 population units in Central Europe in total). Intra-population analysis revealed a high level of gene and nucleotide diversity of studied populations, with values clearly decreasing from north to south. While the Slovak populations were bearing the highest rates of genetic diversity, the lowest values were detected in the Croatian populations. The results of ΦST distances point to a certain similarity of the Slavic population (Slovakia, Czech Republic, Poland, Slovenia, Serbia, Bosnia and Herzegovina), Germanic (Germany, Austria, Switzerland) as well as some groups from Hungary and Romania. As the most distant appeared especially the population of Croatia, which differed from almost all populations included in the study. AMOVA showed that the geographic division of population explains the layout of genetic variation...
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Mitogenomic phylogeography and adaptive evolution of the bank vole Clethrionomys glareolus
Filipi, Karolína ; Kotlík, Petr (advisor) ; Munclinger, Pavel (referee)
This thesis is a part of the project aimed at sequencing the genome and transcriptome of the bank vole (Clethrionomys glareolus). The role of natural selection in the evolution of mitochondrial DNA (mtDNA) has been subject to much discussion; while some studies did not provide evidence that selection affected the phylogeography of the studied species, other considered adaptive evolution important. The bank vole is the key model we use to study the adaptation to climate change. As with other species, the phylogeography of the bank vole has been based on the variation of a small part of mtDNA. The goal of the thesis was to sequence the entire mitochondrial genome for representatives of all main mtDNA lineages of the bank vole using the Sanger and Illumina technologies, and to assess the role of selection and adaptation in the evolution and phylogeography of this species. The adaptive evolution in mtDNA probably was not the main driving force during the postlacial colonization of Europe. However, signatures of adaptive evolution have been found - an amino acid change with possible functional consequences in one gene and an excess of radical changes in physical- chemical properties of amino acids in populations at the latitudinal (northern and southern) extremes of the bank vole distribution. Key...
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Can avian malaria affect the reproductive success of the host?
Krausová, Simona ; Munclinger, Pavel (advisor) ; Vinkler, Michal (referee)
Malarial deseases caused by intracellular parasites of birds is very common. Even if infection doesn't lead to the death of infected individuals, they may suffer alternations of different levels of fitness, which may also consequently harm their reproductive success rates. Infected individuals, due to their poor physical condition, may lay lower quality eggs, breed less viable offspring, have reduced frequency of feeding their chicks, etc. While it may seem that malarial parasites undoubtedly negatively affect their hosts's reproduction, there are numerous studies which do no support such prediction. These differences in individual studies may be due to various testing methods used in the indicated studies. Because of various testing methods, there also may appear other possible problems which can more or less affect the detection rate of malaria parasites.
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