Mutation Spontaneous

A spontaneous mutation is a mutation that occurs in natural conditions when the direct cause of mutagenesis has not been identified.

Spontaneous mutations occur in the cells of organisms constantly, even without exposure to mutagenic factors. They are a consequence of errors during DNA replication, errors in the functioning of DNA repair enzymes, spontaneous chemical transformations of nucleotides and other processes that occur naturally in the cell.

The incidence of spontaneous mutations is usually very low, on the order of 10^{ -5}-10^{ -8} per gene per generation. However, in the sum of the genome of an organism, spontaneous mutations make a significant contribution to the variability of traits in populations.

Most spontaneous mutations are lethal or neutral for the organism. Less often, they lead to the emergence of new useful traits. However, spontaneous mutagenesis is considered the main source of genetic variation in natural populations and an important factor in evolution.