Topic 6: Mutation Flashcards
What is the definition of a mutation?
A mutation is the changes in DNA that can result in no protein or an altered protein being synthesised
What is a single gene mutation and what types exist?
Alteration of a DNA nucleotide sequence which includes substitution, insertion or deletion of nucleotides
Single nucleotide substitutions include what type of mutations?
Missense, nonsense and spice-site mutations
What do you missense mutations result in?
One amino acid being changed for another
A non-functional protein may be produced
Or little effect on the protein
What do you nonsense mutations result in?
A premature stop codon
A shorter protein is produced
What do you splice site mutations result in?
Some Intron being retained
Some exons not included in the mature transcript
What impact do nucleotide insertion or deletion have?
Result in frameshift mutation
All codons after the mutation or changed
All amino acids after the mutation or changed
Cause a major effect on the structure of the protein produced
What are the type of chromosome structure mutations?
Duplication, deletion, inversion and translocation
What happens to the chromosome during duplication mutations?
A section of a chromosome is added from its homologous partner
What happens to the chromosome during deletion mutations?
A section of a chromosome is removed
What happens to the chromosome during inversion mutations?
A section of a chromosome is reversed
What happens to the chromosomes during translocation mutations?
A section of a chromosome is added to a chromosome, not its homologous partner
Why are chromosomal mutations not good?
The substantial changes in chromosome mutations often make them lethal
