Mutations Flashcards
(16 cards)
What are mutations?
Permanent changes to the DNA in genes or chromosomes
What can mutations result in?
No protein or an altered protein being synthesised during gene expression
What do single gene mutations cause?
the alteration of a DNA nucleotide sequence in a gene
What are the 3 single gene mutations?
Deletion of nucleotides
Insertion of nucleotides
Substitution of nucleotides
What are the three types of mutations as a result of nucleotide substitution
Missense mutation
Nonsense mutation
Splice site mutation
What are missense mutations?
They result in one amino acid being changed for another which may result in a non functional protein or have little effect on the protein
What are nonsense mutations?
Result in a premature stop codon being produced which results in a shorter protein
What are splice site mutations?
Of a mutation occurs at a splice site between introns and exons it may result in some introns being retained and/or some exons not being included in the mature transcript
What do nucleotide insertions and deletions result in?
Frameshift mutations
What do frame shift mutations cause?
All codons after mutation will be altered during transcription, in turn altering every amino acid after the mutation site
This has a major effect on the structure of the protein produced
What are the four types of chromosome structure mutations?
Duplication
Deletion
Inversion
Translocation
What is duplication?
Where a section of a chromosome is added form its homologous partner
What is deletion?
Where a section of a chromosome is removed
What is inversion?
Where a section of chromosome is reversed
What is translocation?
Ehre as section of a chromosome is added to a chromosome (not its homologous partner)
What can the substantial changes in chromosome mutations often make them?
Lethal
