Either all the cells carry the mutation or none of the cells carry the mutation
4 of 17
What are the types of mutation?
base substitutions (transitions and transversions), insertions and deletions (frame shifts) and expanding trinucleotide repeats
5 of 17
What is a missense mutation?
when the protein sequence is changed
6 of 17
What is a nonsense mutation?
When the protein sequence is terminated
7 of 17
What is a silent mutation?
When the protein sequence is unchanged.
8 of 17
How is expanding trinucleotide repeats created?
When slippage occurs during DNA replication and repeated regions loop out on the daughter strand, leading to increased copy number of the repeat
9 of 17
What is Fragile X syndrome?
An example of an expanding trinucleotide repeat mutation and is the most common form of inherited mental impairment
10 of 17
Are loss of function mutations recessive or dominant?
Recessive
11 of 17
Are gain of function mutations recessive or dominant?
Dominant
12 of 17
What are conditional mutations?
Mutations that only expressed under certain conditions
13 of 17
What are lethal mutations?
Those the cause premature death.
14 of 17
What causes mutations?
Can be spontaneous (replication errors, natural DNA damage) or induced (radiation or chemical mutagenesis)
15 of 17
What is natural DNA damage?
Depurination (loss of purine base) and Deamination (loss of amino group from a base)
16 of 17
What does the excision repair pathway involve?
Detection of damaged DNA, excision on either side of damaged DNA, polymerization using undamaged strand as template and ligation when the old and new DNA is joined together.
Comments
No comments have yet been made