ITRs are symmetrical DNA sequences found at the ends of certain viral genomes. Each ITR presents the sequence of the other in a reverse complement manner. These sequences play a crucial role, e.g., in AAV production. ITRs serve as recognition sites for the AAV Rep proteins, enabling the formation of the viral replication complex. This complex initiates DNA replication and ensures the production of sufficient viral genomes for packaging. Moreover, ITRs act as packaging signals, guiding the encapsidation of the AAV genome into the viral capsid during production. Production and retainment of intact ITRs is vital for the successful assembly of functional AAV particles.