A mutation is a change in the DNA sequence of an organism.
Understanding Mutations
According to the provided reference, a mutation is defined as:
- A change in the DNA sequence of an organism. This change can alter the genetic instructions that cells follow.
Causes of Mutations
Mutations can arise from several sources:
- Errors in DNA replication during cell division: When cells divide, they must copy their DNA. Mistakes can happen during this copying process.
- Exposure to mutagens: Mutagens are agents that can damage DNA. Examples include:
- Certain chemicals
- Radiation (e.g., UV radiation, X-rays)
- Viral infection: Some viruses can insert their DNA into the host cell's DNA, causing mutations.
Example of Mutation
| Mutation Type | Description | Example |
|---|---|---|
| Point Mutation | Change in a single nucleotide base. | Sickle cell anemia caused by a single base change in the beta-globin gene. |
| Insertion | Addition of one or more nucleotide base pairs. | Some cases of Huntington's disease due to increased repeats of a specific DNA sequence. |
| Deletion | Loss of one or more nucleotide base pairs. | Cystic fibrosis caused by deletion of a specific amino acid in the CFTR protein. |
