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The interaction of lactase persistence and skin depigmentation in connection with the calcium assimilation hypothesis
Grendelová, Gréta ; Černý, Viktor (advisor) ; Brůžek, Jaroslav (referee)
The most recent genetic studies have proven that skin colour of our European ancestors was originally very dark. Skin depigmentation has begun after "out of Africa" time as a result of low levels of the ultraviolet radiation in changed regions at the higher latitudes. Lightly pigmented skin allows sunlight to penetrate human skin more deeply and vitamin D, which is essential for optimal functions of human body, is synthesised by biochemical interaction of ultraviolet radiation and epidermis. A deficit of vitamin D and calcium may be associated with the rickets in children and osteomalacia in adults. Following the correlation of rising depigmentation at the higher latitudes we may notice an increasing number of people with specific metabolic ability known as lactase persistence. Lactase persistence allows the digestion of milk sugar, lactose, in fresh milk in adulthood. It has likely evolved as a substitute in order to compensate for lower amounts of vitamin D in human body. The origin and spread of lactase persistence began around 7,000 years ago after the start of milk production. The oldest evidence of milk production was found in the Middle East. Lately, it has also been supported by the recent genetic analyses. Depigmentation and lactase persistence both began as an adaptation due to changed...
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Consequences of an infectious disease on genetic information in DNA sequences in bats
Nováková, Markéta ; Martínková, Natália (advisor) ; Lučan, Radek (referee)
Whitenose syndrome is an emerging fungal disease of bats causing massive dieoffs in North American populations. The fungus causes lesions on bat skin, mainly on noses, ears and wing membranes. The infection by the fungus is accompanied by serious disruption of metabolism and hibernation physiology that is lethal to bats in North America. European bats seem to survive the disease in greater numbers. Since the fungus is probably of European origin, this study assumes that bats in Europe have developed inheritable defence mechanisms to the disease. The infection by the fungus serves as a strong selective pressure. We tested sequences of 7 genes for signs of positive selection using maximum likelihood approach. We detected past positive selection in the gene for transglutaminase 1.
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Pozitive and negative selection of mitochondrial genome
Svoboda, Matěj ; Kupková, Kristýna (referee) ; Maděránková, Denisa (advisor)
The bachelor thesis engages with problematics of positive and negative selection of mitochondrial genome. Thesis is divided into two parts. First part grapples with theory and explanation of fundamental definitions, in particular understates mitochondrial genome, nucleotide mutation, positive and negative selection and furthermore evolution models. Second part focuses on processing mitochondrial DNA practically and on establishing functions in programming environment R. The emphasis is foremost on gene sequencing alignment and exploring substitutions. Consequently, obtained outcomes are contrasted with PAML and KaKs Calculator programme outcomes.
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Artificial Immune Computational Systems
Neuwirth, David ; Schwarz, Josef (referee) ; Sekanina, Lukáš (advisor)
Artificial immune computational system is a relatively new branch in the area of computer systems. This bachelors thesis presents the fact that we can be inspired by biological immune systems and that we can use their attributes and principles in the artificial immune computational systems. On the following pages you can meet several examples, where and how the principles had been already used. The last part of this work is devoted to implementation of educational material into the lesson ( http://www.stud.fit.vutbr.cz/~xneuwi00/AIS/ ).
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