The Coronaviridae family includes viruses that are considered the causative agents of respiratory infections, and among human RNA viruses have the largest genome. Coronaviruses undergo elusive genetic changes through mutation during replication. A gene mutation is a permanent alteration in the nucleic acid sequence; if it occurs in large numbers, it causes changes in the biological features of a species. Fundamentally, viruses adapt to the human body during replication. Several studies have shown that most mutations do not have much effect on pathogenicity. Sequence diversity in new coronaviruses is very low. However, antigen drift has been observed among some coronaviruses. Most coronavirus mutations occur intermittently in Iran and other countries and have little effect on the pathogenicity of the virus but have increased its rate of transmission. In mutated viruses, deletion of nucleotide sequences has been observed relatively in some reading frames extensively. Studies have shown that the host protein induced mutagenesis through interaction via viral proteins. The most important mutation in SARS-CoV2 compared to the original Wuhan virus was the spike D614G mutation and the lineage of B.1.1.7, 20I/501Y.V1become the dominant and exhibit greater virus spread but did not associate with higher viral loads and morbidity. However, it may affect the effectiveness of the vaccines and mortality rate.