The scientific seminar with the title of Introduction and Guide to CRISPR - Cas9 Genome Editing Technology was conducted by Mr. Eskandar Hossein Nejad, the Ph.D. student of Genetics, in the conference hall of the Shrimp Research Institute of Iran. The CRISPR - Cas9 is a unique and new genome editing technology that can greatly contribute to the advancement of gene therapy. In the CRISPR - Cas9 method, scientists can directly modify the defective gene and insert a healthy DNA. This method makes it possible to insert, remove or replace part of the genome. Some bacteria have a simple CRISPR - Cas9 system for genome editing that is used to respond to invasive agents such as viruses and the process works like the immune system for them.The CRISPR - Cas9 in bacteria breaks down part of the bacterial DNA and helps the bacteria to identify the pathogen in the subsequent invasion.