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Mosaic Codes Essay

Decent Essays

Minimising Errors
Triplet codes are a sequence of three nucleotides on a DNA or an RNA molecule which codes for a specific amino acid. For example, CAG codes for the amino acid Glutamine and TAT codes for the amino acid Tyrosine.
A codon is the base triplets on the mRNA. Each is a copy of the base triplets on the DNA coding strand but in place of the base thymine there is the base uracil (1).
Anticodon is a complimentary sequence to the codon base triplets found in mRNA (it is a mirror image). When the mRNA has passed through s pore in the nuclear envelope and arrived at a ribosome, amino acids are brought by tRNA molecules (1).
Degenerate codes are when there is more than one base triplet for the amino acids, excluding methionine and …show more content…

This leads to deformation of the red blood cell into a sickle-like shape making it relatively inflexible and unable to traverse the capillary beds (7). Degenerate codes can reduce the effects of missense mutations, as there’s a possibility that the nucleotide changed will still code for the same amino acid.

Nonsense mutation: When a point mutation alters a base triplet, and makes it a stop triplet, also known as a stop codon, resulting in a short protein which is unable to function (1). An unwanted stop codon cuts a ribosome's process of polypeptide synthesis along an mRNA strand short, resulting in fragmented incomplete polypeptide strands. These fragmented polypeptide strands do not undergo successful structural folding to form the appropriate structure of the originally-intended protein. For example, if AGT (Aspartic acid) was changed into TAG (stop), the protein would be unable to continue and would break away before it is required to. One disease caused by the nonsense mutation is Cystic Fibrosis. This disease affects the secretory glands, including mucus and sweat glands. The mucus blocks passages in many of the body’s organs causing infections to occur. There are different ways to help try to fix a nonsense mutation from happening, including gene therapy or genome editing for DNA and exon skipping, pseudo uridylation and trans-splicing for RNA.

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