What term is used for any agent that can cause a genetic mutation?

The term "mutagen" refers specifically to any agent that can induce a change in the DNA sequence of an organism, leading to a genetic mutation. Mutagens can be physical agents, such as radiation, or chemical agents, such as certain chemicals or environmental pollutants, which interact with DNA and alter its structure. This alteration in DNA can result in mutations, which may have various effects on the organism, ranging from silent changes to significant alterations that can affect health or development.

In contrast, an allele is a variant form of a gene that might arise through mutation but is not itself a mutagen. Genetic recombination refers to the process by which genetic material is physically mixed during gamete formation, contributing to genetic diversity but not directly causing mutations. A chromosome is a structure composed of DNA and proteins that contains genetic information; while it carries genes and alleles that might be affected by mutations, it is not a cause of mutations. Therefore, "mutagen" is the precise term that encapsulates the concept of agents responsible for inducing genetic mutations.