Mutations Flashcards
What is a mutation?
It is when there are changes in DNA that result in no protein or altered protein being synthesised.
What is involved in a single gene mutation?
It involves the alteration of a DNA nucleotide sequence.
What are examples of single gene mutations?
- Substitution
- Insertion
- Deletion
What are the three types of substitution mutations?
- Missense
- Nonsense
- Splice site
What happens when a missense mutation occurs?
It results in one amino acid being changed for another. Which may result in a non-functional protein or may have little effect on the protein depending on the amino acid that has been changed.
What is an example of a missence mutation?
Sickle cell disease
What happens when a nonsense mutation occurs?
It results in a premature STOP codon being produced which results in a shorter protein.
What is an example of a nonsense mutation?
Duchenne Muscular dystrophy
What happens when a splice site mutation occurs?
It results in some introns being retained or some exons not being included in the mature transcript.
What is an example of a splice site mutation?
beta thatassemia
What happens when a frame shift mutation occurs?
It causes all of the codons and amino acids after the mutation to be changed. It has a major effect on the structure of the proteins produced.
What are the two types of a frame shift mutation?
- Insertion
- Deletion
What is an example of an insertion frame shift mutation?
Tay-Sachs disease
What is an example of a deletion frame shift mutation?
Cystic Fibrosis
What are the four types of chromosome mutations?
- Duplication
- Deletion
- Inversion
- Translocation
