The key difference between mutation and mutagen is that mutation is a change in the nucleotide sequence of the genome of an organism, while mutagen is an agent that is responsible for the development of a mutation.
Sometimes, errors can occur during the DNA replication process. The DNA repair mechanisms present in the cell usually correct these errors. However, certain errors become permanent and heritable. Causes for mutations vary. Mutagens are one such cause. Hence, mutations and mutagens are two terms that describe changes in the nucleotide sequence of the genome of an organism. These changes are both genotypic and phenotypic. Hence, they contribute to the evolution of organisms.
CONTENTS
1. Overview and Key Difference
2. What is a Mutation
3. What is a Mutagen
4. Similarities – Mutation and Mutagen
5. Mutation vs Mutagen in Tabular Form
6. Summary – Mutation vs Mutagen
What is a Mutation?
A mutation is a change in the nucleotide sequence of the genome of an organism. Mutations commonly occur during the replication process of DNA. These are called spontaneous mutations. External mutagens also cause mutations. These are called induced mutations.
Figure 01: Types of Mutations
The cell replication process consists of a DNA error repair mechanism that avoids both types of causes. However, mutations can occur, overriding the correction process. Mutations with positive effects are inheritable. Such mutations could be either beneficial or harmful. Beneficial mutations allow the organism to suit the environment more effectively. Nevertheless, most of the mutations are harmful due to the disruption of the genetic sequence and the normal function of the cell. This could cause diseases and other abnormalities within the body.
The three types of DNA mutations are base substitutions, insertions, and deletions. During base substitution or point mutations, three subtypes of mutations can happen. They are silent mutations, missense mutations, and nonsense mutations. Some mutations can be lethal, but some can be neutral with no significant effect.
What is a Mutagen?
Mutagen is an external agent that causes a change in the nucleotide sequence of the genome of an organism during the process of DNA replication. These changes in the genome sequence lead to the development of mutations. Hence, mutagens are genotoxic. The effect of mutagens on the DNA replication process and transcription can cause lethal effects.
Figure 02: Mutagenesis
However, depending on the mutagen type, the consequences vary. The main types of mutagens are physical mutagens, chemical mutagens, and biological agents. Physical mutagens are X-rays, UV radiation, and radioactive decay. Chemical mutagens are base analogs, intercalating agents, alkylating agents, deaminating agents, reactive oxygen, and nitrogen species. Biological agents are transposons, viruses, and bacteria.
What are the Similarities Between Mutation and Mutagen?
- Mutation and mutagens are involved in the DNA replication process.
- The effect of both types affects the transcription and folding of DNA.
- They cause changes in the nucleotide sequence of the genome of an organism.
- Moreover, they cause heritable changes to the genome.
- Furthermore, they may result in beneficial and harmful changes to the cell and genome.
- Both types contribute to evolution.
What is the Difference Between Mutation and Mutagen?
The key difference between mutation and mutagen is that mutation is a change in the nucleotide sequence of the genome of an organism, while mutagen is an agent that is responsible for the development of a mutation. Furthermore, the main types of mutations include base substitutions, insertions, and deletions. Whereas, the main types of mutagens include base analogs, DNA reactive chemicals, metals, intercalating agents, and biological agents.
The below infographic presents the differences between mutation and mutagen in tabular form for side by side comparison.
Summary – Mutation vs Mutagen
A mutation is a change in the nucleotide sequence of the genome of an organism. Mutagen is an agent that causes a change in the nucleotide sequence of the genome (mutation) of an organism. Thus, this is the key difference between mutation and mutagen. Mutations and mutagens are two terms that describe the change in the nucleotide sequence of the genome of an organism. These changes are both genotypic and phenotypic. Hence, they contribute to the evolution of organisms. Mutations with positive effects are inheritable. Such mutations can be either beneficial or harmful. Mutagens are genotoxic. Depending on the mutagen type, the consequences vary. So, this summarizes the difference between mutation and mutagen.
Reference:
1. “Mutagen.” Genome.gov.
2. “Mutation.” Encyclopædia Britannica, Encyclopædia Britannica, Inc.
Image Courtesy:
1. “Forward mutagenesis” By © 2014 Lena M. Kutscher and Shai Shaham. – Kutscher L. M., Shaham S. Forward and reverse mutagenesis in C. elegans (January 17, 2014), WormBook, ed. The C. elegans Research Community, WormBook, doi/10.1895/wormbook.1.167.1. (CC BY-SA 2.5) via Commons Wikimedia
2. “Point mutations-en” By User:Mikey641 – Own work using: file:Point mutations-en.png This W3C-unspecified vector image was created with Inkscape (CC BY-SA 4.0) via Commons Wikimedia