What advantage can you see to having more than one codon coding for the same amino acid?

Redundency





Genetic diseases are often caused by the lack of a gene that creates something your body needs. The most famous is the lack of the gene that produces insulin; in diabetes. If you had redundency in the gene that produces that insulin then you would have a better chance of not suffering genetic caused diabetes (Type 1 diabetes where the cells are destroyed by a body autoimmune action; http://en.wikipedia.org/wiki/Diabetes).





According to Wikipedia: http://en.wikipedia.org/wiki/Codon


"The genetic code is the set of rules by which information encoded in genetic material (DNA or RNA sequences) is translated into proteins (amino acid sequences) by living cells. Specifically, the code defines a mapping between tri-nucleotide sequences called codons and amino acids; every triplet of nucleotides in a nucleic acid sequence specifies a single amino acid. Because the vast majority of genes are encoded with exactly the same code (see #RNA codon table), this particular code is often referred to as the canonical or standard genetic code, or simply the genetic code, though in fact there are many variant codes; thus, the canonical genetic code is not universal. For example, in humans, protein synthesis in mitochondria relies on a genetic code that varies from the canonical code.





It is important to know that not all genetic information is stored as the genetic code. All organisms' DNA contain regulatory sequences, intergenic segments, chomosomal structural areas, which can contribute greatly to phenotype but operate using a distinct sets of rules which may or may not be as straightforward as the well-defined codon-to-amino acid paradigm which underlies the genetic code."





Remember that genes don't control everything they only set it up and other body process can produce other amino acids and other needed items. Genes is only one way the body makes sure it has the equipment to produce what it needs.

What advantage can you see to having more than one codon coding for the same amino acid?
The extra codons mean the code is more resilient- small errors can still result in the same protein being produced. The other advantage is that in some cases, a single strand of genetic material might code for more than one protein or enzyme, depending on how it is read. This means that one method of reading will produce the same output, but the second or third method of reading (starting from a different place on the strand) can produce other, entirely different materials. This concept is like a palimpsest.
Reply:Redundancy.
Reply:1) theres twenty amino acids, which means 1 and 2 codons aren't suffuciant enough to give 20 different amino acids


2) allows for mutation absorbency. With more then one (3 codons) you can have one amino acid coded my multiple triplets, and a mutation in one codon in one of the triplets usually just changes it to one of the other triplets
Reply:I'm no expert on this but if you have probably noticed that usually it's the third nucleic acid in "degenerate" codons that can be changed without affecting the resulting amino acid. This means that some DNA mutations are "silent".





Very evolution might have selected for this as it eliminated some lethal mutations.