Mutagenics: What are they? Classification, Types, Importance and Mutations

Also called mutagens, they are elements that can be chemical, physical, or biological, capable of transforming the genetic information of a living organism.


Mutagenic agents cause not all mutations. According to its origin, the modifications can be:


Because of errors in DNA repair and recombination, some are called ” spontaneous mutations .”


It is the result of the intervention of mutagens that can be physical, chemical, or biological that change the genetic information of an organism.

Types of Mutagenic Agents


They are chemical compounds apt to produce a violent alteration in the structures of DNA.

Certain foods and substances of daily use, such as tobacco smoke, dyes, and some medicines, contain chemical mutagens.


It refers to those who can change their host’s genetic material sequences.


Preparations used in the prevention and therapeutic medicine, such as antitoxins, vaccines, blood, and serum, are possible sources of biological mutagens.

Microorganisms, especially viruses, are also sources of biological mutagens. It is proven that viruses can cause chromosomal abnormalities.


They are radiations that can cause a modification in the chain and the DNA configuration.

An example of this is ultrasound, with 400,000 vibrations per second since they have caused mutations that produce structural chromosome variations.

This section includes atomic radiation and X-rays that produce sterility in living beings. They also affect tissues such as muscles, bones, nerves, kidneys, liver, etc.

Radiation is a physical process through which energy travels through space. There are two variations:

  • Electromagnetic:  Consists of electric power waves. Examples: gamma rays, X-rays, and UV radiation.
  • Corpuscular: It is composed of atomic and subatomic particles that travel at enormous speeds and cause deterioration when colliding with other particles, including biological molecules. They would be α particles and β-particles.

Sources of radiation

Humans are constantly exposed to radiation that can cause mutation. The effects of radiation at a biological level are, in general lines changes that are generated at various levels of the organization, such as molecules, organelles, and cells.

Microorganisms, especially viruses and some chemical agents, can be potential biological agents.

Viruses can produce abnormalities in chromosomes, from a simple break to the spraying of chromosomes, as some studies have shown. For this reason, vaccination with a live virus can be a significant risk.

What damage do mutagenic agents produce?

They can produce alterations that lead to diseases such as cancer.

The somatic mutation that originates where the oncogenes that affect the regulatory proteins of cell division are altered is the cause of cancer.

Importance of mutations

  • Genetic variation
  • Evolution.

How do mutations originate?

Mutations occur randomly in nature. Although the causes are imprecise, some external agents are known that can produce modifications.

Types of cells in which the mutations originate:


The somatic cells are what make up the organism. A mutation in a cell of this type can cause changes in the organism, but when the individual dies, it disappears.

Cancer is an example of a mutation in a somatic cell.


It refers to sex cells, such as sperm and eggs. A mutation in a cell of this type can cause an inheritable alteration.

The mutations that occur in a cell resulting from the division of the zygote are relevant at an evolutionary level.

There are three types of mutations:

Point mutations:

Mutations in non-coding sequences: These are mutations in regulatory regions that do not encode proteins.

Chromosomal mutations:

They are alterations in the number and order of genes within chromosomes. They originate by the duplication or elimination of genes or segments of a chromosome and the relocation of the genetic material within the chromosomes.

Genomic mutations:

Mutations in coding sequences:  The common cause of its origin is the bad separation of the chromosomes during meiosis.

The chromosomal endowment of an individual is affected by this type of mutation. Individuals that have a genomic mutation have a different number of chromosomes in their cells than in their species.