Mutations and genetic disorders Flashcards
What is a mutation
changes in the DNA that can result in no protein or an altered protein being synthesised
What do single gene mutations alter
The DNA nucleotide sequence
What is a substitutation mutation
one or more nucleotides are replaced
What is an insertion mutation
one or more nucleotides are added
What is a deletion mutation
one or more nucleotides
How is the mRNA code affected by a single nucleotide insertion
All codons after the mutation point are changed
How is the protein affected by a single nucleotide insertion
All amino acids after the mutation point are changed
How is the mRNA code affected by a single nucleotide deletion
All codons after the utation point are changed
How is the protein affected by a single nucleotide deletion
All amino acids after the mutation point are changed
What si the effect of a frame shift mutation
All the codons and all the amino acids after the mutation are changed this has a major affect on the structure of the protein produced
How is the mRNA code affected by a single nucleotide substitution
One codon
How is the protein affected by a ingle nucleotide substitution
One amino acids
What is the cause of a substitution missense mutation
Single nucleotide replaced
What is the chnage in the mRNA code due to a substitution missense mutation
one codon is changed
What si the chnage to polypeptide chain due to a substitution missense mutation
one amino acid is replaced with another
What is the change in the mRNA due to substitution nonsense mutation
one codon is replaced with a premature stop codon
What si the chnage to polypeptide chain due to substittution nonsense mutation
Shorter protein is produced because translation ends prematurely
What does splice site mutations result in
Some introns being retained and or some exons not being included in the mature transcript
What do nucleotide insertions or deletions result in
Frame shift mutation
What do frame shift mutations cause
All of the codons and all of the amino acids after the mutations to be changed
What is translocation
a section of a chromosome breaks off and becomes attached to a chromosome not its homologous partner
What is inversion
A section of chromosomes is reversed
What is deletion
A section of chromosome is removed
What is duplication
a section of a chromosome is repeated or part of a chromosome breaks off and reattached to its homologous partner
what are the consequenced of when chromosome structures are altered
The substantial changes in chromosome mutations often make them lethal
Waht si the cause of a substitution splice site mutation
single nucleotide replaced
What dies nonsense mutations result in
premature stop codon being produced which results in a shorter protein
What dies missense mutations result in
one amino acid being changed for another which may result in a non functional protein or have little effect on the protein
How can you know if a fragment is not from either end of a gene
there is no start or stop codon
What word is used to describe a mutation which results in the addition of an incorrect amino acid into a protein
missense
