Defective Viruses

Defective viruses are viruses that cannot complete a normal virus life cycle due to a missing or incomplete gene or gene sequence. These viruses are observed to exhibit characteristics of both viruses and cellular organisms. They are of biological significance as they act as a starting point for understanding the structure, evolution and diversity of viruses, as well as a valuable tool in the development of gene therapy and cancer treatments. Defective viruses are used in gene therapy by serving as a vector to deliver corrective gene sequences to the patient and have been used to develop various cancer immunotherapies.