Mutations of DNA Flashcards
What does a mutated gene give
Gives an abnormal or no protein gene product creating an altered phenotype
Do all mutations affect us
Mutations range from no effect on protein to completely disable protein. Not all mutations affect protein function so not all mutation will affect us.
Passed on traits of the dominant or recessive is a disabled proteins
they are the recessive traits, thats why two of them are needed for it to be present
Lauri and Delbruck method
Did an experiment to see if mutations are directed by the environment or mutations are random events
What did lauri and delbruk discover
That mutations are random events
Explain lauri and delbruk
They figured out that there was already a mutation that happened in a previous generation to be bacteria resistance. That phage passed it on allowing other phages to receive that mutation making them bacteria resistance so when the bacteria was introduced they were able to survive it and everything was killed off.
-Phages did not become bacterial resistance once the bacteria became introduced it was already resistant
Transition Mutation
Go from A-T at a specific location to G-C or vise versa
-a incorrect base gets placed with a T and proofreading did not kick it out then they divide eventually so now we have 1 normal chromosome and another has has a GC that doesn’t look like anything wrong but if it is one an important protein that requires a specific sequence it can cause harm
Transversion Mutation
Bases get flipped around
When do DNA mutations happen
During the S phase of the cell cycle… when DNA is copied
Are all mutations very dangerous
The mutations that we see today are ones that our body can deal with. If it something that is very sever our body would select against it… we would not have made it past utero
Missense Mutation
Change base creating a different mRNA creating a whole new protein
What is the wild type
The normal type
Not mutation strand
Do missense mutations always have an effect
It depends on what the amino acid get changed to. If it get changed and it doesn’t really affect is shape or how it folds it no much happens. It it affects how it folds and shapes then its complete devastation
Nonsense mutation
a change in the base that creates a new mRNA that forms a stop codon
Example of missense mutation
Sickle cell anemia, Lesch-Nyham Syndrome
