Unit 1-Mutations Flashcards
Changes in the genome
Mutations
Result of mutations
No protein expressed or an altered protein expressed
Alteration of a DNA nucleotide sequence (affects a few bases)
Single gene mutation
Types of single gene mutations
Substitution
Insertion
Deletion
One nucleotide is replaced by another nucleotide, only one amino acid is affected.
Substitution
An extra nucleotide is added to the sequence, whole protein is affected
Insertion
One nucleotide is removed from the sequence, whole protein is affected.
Deletion
Occurs after a substitution, where the altered codon codes for an amino acid which still makes sense, but not the original sense.
Missense mutation
Occurs after a substitution, where the codon used to code for an amino acid but now codes for a stop codon.
Nonsense
A mutation which causes one or more nucleotides to be inserted, substituted or deleted from a site of the sequence where introns are usually removed.
Splice site mutation
Mutations which cause a change in the whole sequence after the mutation site (deletion or insertion)
Frame shift mutations
Alteration to the structure of one or more chromosomes
Chromosome structure mutation
Types of single gene mutations
Substitution
Insertion
Deletion.
A section of a chromosome becomes detached and the information is lost.
Deletion
A section of DNA is repeated on the chromosome
Duplication
