5.1 Effects of Mutation I

What is deletion mutation?

One or more base pairs are deleted

What is a frameshift mutation?

A mutation resulting from insertion or deletion of a group of base pairs that is not a multiple of three and which therefore changes the frame in which translation occurs

What is ‘insertion mutation’?

One or more base pairs are inserted

What is ‘inversion’?

2 or more base pairs are excised and reinserted in opposite orientation

What is ‘nonsense mutation’?

An alteration in a nucleotide sequence that changed a triplet coding for an amino acid into a termination codon

What is ‘missense mutation’?

Mutation that converts a codon for one amino acid into a codon for a second amino acid.

What is another word for missense mutation?

Nonsynonymous mutation 

What is a ‘point mutation’?

Single base pair change in DNA

What is a ‘readthrough mutation’?

A mutation that changes a termination codon into specifying an amino acid, and hence results in readthrough of the termination codon

What is the ‘second site reversion’?

A second mutation that reverses the effect of a previous mutation in the same gene although without restoring the original nucleotide sequence.

What is a ‘silent mutation’?

A change in a DNA sequence that has no effect on the expression or functioning of any gene or gene product 

What is ‘synonymous mutation’?

A mutation that changes a codon into a second codon that specifies the same amino acid 

What is a ‘transition’?

A point mutation in purines to purines OR pyrimidines to pyrimidines

What is a ‘transversion’?

A point mutation in purine to pyrimidine, or vice versa

Why are some mutations important?

Important during evolution / for diversity of organisms