HLADEK, Miroslav: Comparison of some methods of DNA isolation from spruce seeds and variability above 1b/c used by PCR-RFLP. [Bachelor´s thesis] – Technical University in Zvolen. Faculty of Forestry; Department of Phytology. – Tutor: Ing. Diana Krajmerová, PhD. Zvolen: TUZVO, 2020, 55 p.This work is divided into five chapters. The aim of this work was to isolate pure, high molecular weight DNA from spruce seed based on selected methods with a focus on the mtDNA variability analysis. It points out different techniques of DNA isolation of selected spruce seed sources and compares individual samples in order to identify the variability by using PCR-RFLP. The first chapter dealt with the current position of spread of Norway spruce and the influence of the human factor on its genetic differentiation. We also pointed out to the definition of DNA isolation. The polymerase chain reaction method, which serves to amplify (multiply) DNA molecules, was also clarified. Also a restriction analysis was mentioned along with its main advantages and disadvantages. The electrophoresis process was also mentioned. The second chapter is focused on defining the thesis goal. The third chapter is devoted to the methodology. The content of the fourth chapter is an analysis of DNA extraction of selected samples of Norway spruce. The CTAB method with proteinase K, the CTAB method without proteinase or sbeadex were used. Subsequently, the variability of the samples was assessed by PCR-RFLP. In the discussion, the examined situation in the DNA variability difference of spruce seeds in Slovakia and Poland was evaluated In conclusion all findings are summarized and the results of analysis are evaluated.