Mutations Flashcards
Define a mutation
Changes in the DNA
The type of mutations that arise from the alteration of DNA
nucleotide sequence?
Single gene mutations
Name the three types of single-gene mutations
substitution, insertion and deletion
Name the three different nucleotide substitution mutations
Missense, nonsense and splice-site
What happens as a result of a missense mutation?
One amino acid is changed for another
How do missense mutations
affect the protein produced?
It may result in a non-functional
protein or have little effect on the
protein
What happens as a result of a
nonsense mutation?
One amino acid codon is replaced
by a stop codon
How do nonsense mutations affect
the protein produced?
Produces a shorter protein
What are splice-site mutations?
Mutations that result in some
introns being retained and/or some
exons not being included in the
mature transcript
Name the 2 frameshift mutations
Insertion and deletion
How do frame-shift mutations
affect the protein strand being
produced?
They cause all the codons and
therefore amino acids after the
mutation to be changed
Name 4 the different chromosome
structure mutations
Duplication, deletion, inversion and
translocation
What is a duplication mutation?
Where a section of a chromosome
is added from its homologous
partner
What is a deletion mutation?
Where a section of chromosome is
removed
What happens to the chromosome in
an inversion mutation?
A section of a chromosome is
reversed