A point mutation is when a single DNA base pair is changed to a different base pair.

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- Point Mutations
- Silent Mutations
- Missense Mutations
- Conditional Mutations
- Nonsense Mutations
- Frameshift Mutations

Types of Mutations

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Point Mutation

Missense mutations in the DNA cause a different amino acid to be translated after translation. The change in the amino acid may or may not affect the protein function depending on the location and chemical change in the amino acid residue in the protein. 

Missense Mutations

Conditional mutations are missense mutations where the phenotype is only visible in different environmental conditions.

Conditional Mutation

Nonsense mutations are a change in the DNA from an amino acid codon to a stop codon. This causes a protein to be shorter than the native form and it may not be functional anymore. 

Nonsense Mutations

Frameshift mutations are insertions or deletions of nucleotides into the DNA that affect the reading frame of the codons. This shifts the codons that the ribosome reads so it may code for a different protein or a premature stop codon. These mutations usually code for nonfunctional proteins.

Frameshift Mutations

Silent mutations in the DNA have no effect on the protein's structure because the mutation codes for the same amino acid prior to the mutation. This is due to redundancy in the genetic code. 

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