gene mutation Flashcards
(12 cards)
define mutation
change in quantity or structure of DNA in an organism
define gene mutation
change or rearrangement of nucleotide bases in DNA
what are the 6 types of gene mutation
base substitution
base addition
base inversion
base deletion
base duplication
base translocation
what 3 types of gene mutation can be described as frame shift
- base addition
- base deletion
- base duplication
what can be the 3 effects of a base subsitution
- stop codon is formed and the polypeptide is not complete
- codon for a different amino acid is formed
- codon for the same amino acid is formed
what are the effects of a base addition
- frame shift to the right
- alters whole sequence of amino acids
primary, secondary, tertiary structure of protein changed
structure and function of a protein changed
high chance of changing phenotype
what are the effects of a base inversion
- affects amino acid sequence at this part but not before or after
- codon different = different amino acid
- codon same = same amino acid
- stop codon
what are the effects of a base deletion
- frame shift to the left
- alters whole sequence of amino acids
- primary, secondary, tertiary structure changed
- change in function and shape
HIGH chance of changing phenotype
what are the effects of a base duplication
- frame shift to the right
- alters whole sequence of amino acids
different primary, secondary, tertiary structure - different shape and function
HIGH chance of changing phenotype
what is the mechanism for a base translocation
sequence of bases separated from DNA on one chromosome and added to DNA of a different chromosome
what are the effects of a base translocation
significant effect on gene expression leading to abnormal phenotype
describe 3 causes of mutation (3 marks)
- arise spontaneously during DNA replication
- high energy ionising radiation
- chemicals
