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How would mutation affect transcription/translation?

How would mutation affect transcription/translation?

I'm stuck on writing a 6 marker for this. Please help.
Transcription and translation base on genes, the chromosomes to be exact. The chromosome is constructed by the DNA. The DNA has the so called nucleobases. A mutation changes those nucleobases inside of the DNA. To make a DNA to an RNA by transcription, it has to be created the complementary bases of RNA. For this step, the transcription has to 'read' the nucleobases of DNA. If the RNA is done, the translation synthesizes the protein on the basis of the given bases of RNA.

Guess, you understand what the consequence of mutation is: by changing the nucleobases of DNA, completely different complementary bases for RNA are created and so a different RNA too (step of transcription). And a different RNA causes a different protein in turn (step of translation).
(edited 5 years ago)
Reply 2
In addition to the previous answer by @Kallisto, it might also be worth mentioning different types of mutations. Point mutations can either be the insertion, deletion or substitution of a single nucleotide. The substitution of a single nucleotide can alter the codon, which can lead to a different amino acid being produced - this is known as a missense mutation. Not all missense mutations alter the function of the protein though, if both amino acids have similar properties (e.g. are both hydrophobic) It is also worth noting that not all base substitutions result in a missense mutation, some can be a silent mutation. This is because the genetic code is degenerate/redundant - multiple different codons (base triplets) can code for the same amino acid during translation. Also, the insertion or deletion of a number of nucleotides not divisible by three results in a frameshift mutation - the reading frame is altered and therefore every amino acid after the mutation will be altered. This can lead to the production of a premature stop codon, leading to the formation of a truncated protein - this is known as a nonsense mutation. Of course, frameshift mutations lead to the production of a protein with a completely different tertiary structure, and will be non-functional. Finally, insertions/deletions of a number of nucleotudes divisible by three results in an in-frame mutation; the reading frame is preserved and it will lead to the insertion/deletion of a number of amino acids. This has less functional consequences than a frameshift mutation.
Reply 3
Original post by Kallisto
Transcription and translation base on genes, the chromosomes to be exact. The chromosome is constructed by the DNA. The DNA has the so called nucleobases. A mutation changes those nucleobases inside of the DNA. To make a DNA to an RNA by transcription, it has to be created the complementary bases of RNA. For this step, the transcription has to 'read' the nucleobases of DNA. If the RNA is done, the translation synthesizes the protein on the basis of the given bases of RNA.

Guess, you understand what the consequence of mutation is: by changing the nucleobases of DNA, completely different complementary bases for RNA are created and so a different RNA too (step of transcription). And a different RNA causes a different protein in turn (step of translation).


Thanks I was stuck on that. :smile:
Original post by Anouka
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You are welcome! I am (almost) very good in helping students when it matters in genetics.

Original post by Jpw1097
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Nice additions to my reply. Didn't know those details in this extent not anymore. Been a while that I got this in such an accuracy

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