Unit 1 Topic 6- Mutations Flashcards
What is a mutation?
A change in the DNA that can result in no protein or an altered protein being synthesized
What are the 2 main types of mutation?
Single gene (point) and chromosome structure
What are the 3 types of point mutations?
Missense, nonsense and splice site
What is a single gene mutation?
A change in a DNA nucleotide that results in the alteration of a DNA nucleotide sequence
What is a missense mutation?
This is when one amino acid is changed for another, this may result in a non functional protein or have little effect on the protein
What is a nonsense mutation?
A mutation that results in a premature stop codon which shortens the protein
What is a splice site mutation?
When some introns are retained and/or some exons are not included in the mature transcript
What are the 4 types of chromosome structure mutation?
Duplication, deletion, inversion and translocation
What is duplication?
When a section of a chromosome is added from its homologous partner
What is deletion (chromosome)?
When a section of a chromosome is removed
What is inversion?
When a section of a chromosome removed, rotated 180° and reinserted into the same chromosome
What is translocation?
When a section of a chromosome is added to a chromosome that is not its homologous partner
Can chromosome mutations be lethal?
Yes
What are frame shift mutations?
When as a result of insertion or deletion all of the codons and all amino acids are changed which has a major effect on the structure of the protein
What are the stop codons?
UAG, UAA and UGA