Agricultural crop plants are a source of nutrition, so growers have always strived to improve existing traits. Conventional breeding has acquired many improved characteristics of cultivated plants, but the process is time consuming and also results in unwanted modifications. Recent progress in biotechnology have led to improvement of only desired traits in plants. New methods are precise and can be used to edit specific genes in a plant. The most important methods of genome editing are zinc finger nucleases (ZFN), TAL effector nucleases (TALEN), and cluster regulary interspaced short palindromic repeats (CRISPR / Cas9). In my work I have presented achievements in genome editing using CRISPR / Cas9 and TALEN and also described the regulatory framework of new breeding techniques (NBTs) in the European Union and some other countries. The artificial TALEN consists of two TALE binding domains and a cleavage domain represented by the FOK1 enzyme. TALEN recognizes the target site of two DNA binding domains, FOK1 enzyme cuts the double stranded DNA. CRISPR / Cas9 is a simple and effective method for site-specific mutagenesis. It is based on the principle of the adaptive immune system of bacteria and archaea, which they have developed as a defense mechanism against invading pathogens. Synthesized CRISPR / Cas9 consists of sgRNA and Cas9 protein. sgRNA leads Cas9 to the target site, and Cas9 is responsible for double strand break, thereby preventing the invading virus from duplicating.
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