ccch 7 Flashcards
Mutation
changes in the nucleotide sequence of DNA
spontaneous mutation
natural, rep errors, reactive oxygen from metabolism
induced mutation
any chemical or physical agent that causes hella mutations
mutations importance
- genetic variation
- advantage consequences
- important tools for understanding genes
point mutations
single nucleotide alterations, (nucleotide substitution)
bigger mutations
trinuclotide repeats, insertions, deletions, chromo rearrangement
mutation hotspot
places that are more likely to mutate
transition mutation
pyrimidine/purine replace with like
transversion
purine replace with pyrimidine, or vise versa
post mutations become permanent if
its replicate into a DNA sequence (not repaired)
types of mutations
silent mutation, missense mutation, nonsense mutation
missense mutation
amino acid swapped for another
nonsense mutaiton
amino acid to stop codon
sickle cell is caused by
missense mutation, A to T (tranvsersion)
insertions and deletions
leads to adding/subtraction amino acids, frameshift
cystic fibrosis is caused by
deletion mutation, CFTR cannel mutation
frame shift
insertion or deletion causing the shift in a frame, usually harmful
RTH thyroid hormone sensitivity
caused by frameshift, goiter, abnormal psychology
mutation need to be in - to have an effect
gene coding region or area important to it, needs to not be silent
trinucelotide repeats, most common
CGG, CAG, GAA
usually make triple helix, neurological disorders
fragile x and Huntingtons is caused by
trinucleotide repeats
repeats caused by
unequal cross over, slipping during DNA replication
unequal crossing over
one is short and other is longer
slipping durring DNA rep
forms a slipped structure during replication
mutagen DNA damage
single base changes, structural distortion , DNA backbone damage
single base changes cause (what types of mutations)
single base conversion, alkylation, oxidation, minor effect of structure
deamination
mutagenic single base change, most frequent, hydrolytic, C to U is common
alkylation
adds methyl groups, nitrosamines
GC to AT
oxidation
gains oxygen bond, radiation
GC to TA
structural distortion
UV radiation causes Tymine dimers, creates backbone bulge and fucks everything up