Three different types of common mutagens are observed in nature- physical and chemical mutagens agents and biological agents. Physical Agents: Heat and radiation. Chemical Agents: Base analogs. Biological Agents: Viruses, Bacteria, Transposons.

Types

• Physical mutagens.
• DNA reactive chemicals.
• Base analogs.
• Intercalating agents.
• Metals.
• Biological agents.
• Bacterial.
• Yeast.

A mutagen is a chemical or physical phenomenon, such as ionizing radiation, that promotes errors in DNA replication. Exposure to a mutagen can produce DNA mutations that cause or contribute to diseases such as cancer.

Types of mutagens include radiation, chemicals, and infectious agents. Mutations may be spontaneous in nature.

Two major categories of mutations are germline mutations and somatic mutations.

• Germline mutations occur in gametes. These mutations are especially significant because they can be transmitted to offspring and every cell in the offspring will have the mutation.
• Somatic mutations occur in other cells of the body.

Types of Changes in DNA

In Summary: Major Types of Mutations Mutations can be of many types, such as substitution, deletion, insertion, and translocation.

If a point mutation changes the amino acid to a “stop,” it’s called a NONSENSE mutation. Deletion and insertion may cause what’s called a FRAMESHIFT, meaning the reading frame changes. These are typically one of the most serious types of mutations.

Insertion or deletion, which leads to frameshift mutation is more damaging. It causes changes in the subsequent amino acid sequences in a polypeptide chain.

Substances

• Carcinogens.
• Ethylene Dichlorides.
• Flame Retardants.
• Hair Dyes.
• Hydrocarbons, Halogenated.
• Mutagens.
• Furylfuramide.
• Ethylene Dibromide. DNA.

A Mutation occurs when a DNA gene is damaged or changed in such a way as to alter the genetic message carried by that gene. A Mutagen is an agent of substance that can bring about a permanent alteration to the physical composition of a DNA gene such that the genetic message is changed.

Mutations can be induced in a variety of ways, such as by exposure to ultraviolet or ionizing radiation or chemical mutagens. Since the 1950s, over 2,000 crop varieties have been developed by inducing mutations to randomly alter genetic traits and then selecting for improved types among the progeny.

Examples of mutations in animals are those born with extra body parts, e.g. two-headed snake, four-legged ducks, and a cyclops kitten. Often, these kinds of mutations lead to the death of the animal soon or a few days after its birth.

To artificially induce hereditary changes in plants, either physical or chemical agents are used. Ionizing radiation is a widely used physical agent to treat the seeds and other plant material of crops to create heritable mutations.

Plant mutations, known as sports, breaks, or chimeras, are naturally occurring genetic mutations that can change the appearance of the foliage, flowers, fruit or stems of any plant.

Summary. Like all living organisms, plants use deoxyribonucleic acid (DNA) as their genetic material. The DNA in plant cells is found in the nucleus, the mitochondria and the chloroplasts. DNA is a coded set of instructions for making RNA.

In this context, the major aim in mutation-based breeding is to develop and improve well-adapted plant varieties by modifying one or two major traits to increase their productivity or quality. Both physical and chemical mutagenesis is used in inducing mutations in seeds and other planting materials.

The ultimate source of all genetic variation is mutation. Mutation is important as the first step of evolution because it creates a new DNA sequence for a particular gene, creating a new allele. Recombination also can create a new DNA sequence (a new allele) for a specific gene through intragenic recombination.

Most chemical mutagens are alkylating agents and azides. Physical mutagens include electromagnetic radiation, such as gamma rays, X rays, and UV light, and particle radiation, such as fast and thermal neutrons, beta and alpha particles.

The most commonly used chemical mutagens are alkylating agents such as ethylmethane sulfonate and N-methyl-N-nitrosourea that induce point mutations in DNA.