Introduction During the last decade, the gene editing tool CRISPR-Cas9 (clustered regularly interspaced short palindromic repeats and CRISPR-associated protein 9) has revolutionized the field of biology.[1, 2] The Cas9 protein contains two endonuclease domains capable of inducing a double-stranded break (DSB) at a specific DNA target region. The protein binds to a single-stranded RNA (ssRNA) known as the guide RNA (gRNA), whose sequence is designed to be complementary to the target region next t...