1.4 Mutations Flashcards
What is a mutation?
A change to an individuals DNA
Name 2 types of Mutations
Gene Mutation and Chromosome Mutation
How is an individual defined as a mutant?
When there is a change in the genotype due to a mutation that results in a change to the phenotype
Name 2 examples of mutagenic agents?
- Chemicals (Mustard Gas)
- Radiation (UV and X-Rays)
What does a single gene mutation involve?
A change in the sequence of nucleotide
Name 3 examples of single gene mutation
- Substitution
- Insertion
- Deletion
What are the 3 types of substitution mutation?
- Missense
- Nonsense
- Splice-site
What is a missense mutation?
One nucleotide changed which results in one amino acid being changed for another. May result in a non-functional protein or have little effect on the protein
What is a nonsense mutation?
Replacing an amino acid codon with a premature stop codon. Results in a shorter protein
What is a splice-site mutation?
Some introns are retained or some exons are removed from mature transcript
What are 2 examples of frameshift mutations?
- Insertion
- Deletion
What does a frameshift mutation lead to?
A major change because it causes a large portion of the genes DNA to be misread
What happens to every amino acid in a frameshift mutation?
They are affected
What happens to the protein during a frameshift mutation?
Every amino acid is affected meaning that the protein is usually non- functional
What are 4 examples of a chromosome mutation?
- Deletion
- Duplication
- Inversion
- Translocation
