DNA Repair Flashcards
what is a point mutation?
change from one base to another
what is a missense mutation?
base change produces a different amino acid
what is a nonsense mutation?
base change produces a stop codon
what is a transition mutation?
pyrimidine to pyrimidine or purine to purine
what is a transversion?
purine and pyrimidine interchanged
where do somatic mutations occur?
in any cell except germ cells and not inheritable
where do germ line mutations occur?
in gametes
what are autosomal mutations?
occur within genes located on autosomes e.g. not x or y
how does a loss of function occur from a mutation?
target gene may be inhibited or not binding where it is supposed to be so less protein production
how does a gain of function occur from a mutation?
gene expression when not usually expressed, interact with other proteins so more produced
how might imperfect replication cause mutations?
DNA polymerase makes an error, process not accurate enough
what are the types of replication damage?
replication slippage and tautomeric shifts
what is replication slippage?
loop formed in the template strand so polymerase misses it out and insertions and deletions occurs
where is slippage most common?
in common repeat sequences called hot spots
how can hot spots cause genetic diseases?
contribute to hereditary diseases such as huntingtons
