The genetic code assigns RNA codons to amino acids or termination signals. Four possible nucleobases at each of three positions give codons. In the standard genetic code, 61 specify amino acids and three are stop codons; several codons can specify the same amino acid. Variants exist, so state which genetic code is being used. See Clark, Douglas and Choi: genetic code assignments and variants.
A codon is a three-nucleotide unit read in a specified reading frame during biological translation. For example, GCU specifies alanine in the standard genetic code. Its letters are read .
In the standard genetic code, UAA, UAG and UGA are stop codons: they signal termination of biological translation rather than an amino acid assignment. See Clark, Douglas and Choi: stop codons.
A reading frame specifies how consecutive nucleotides are grouped into codons. Starting at position 1 of AUGGCUUAA gives AUG / GCU / UAA; starting at position 2 gives UGG / CUU with AA left over. The letters are unchanged but the groups differ. A possible grouping alone does not establish an actual biological translation initiation site.
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The genetic code is a set of rules that defines how the information encoded in DNA or RNA sequences is translated into proteins, which are essential for the structure and function of living organisms. It is essentially the language of genetic information. Here are some key points about the genetic code: 1. **Codons**: The genetic code consists of sequences of three nucleotides, known as codons. Each codon corresponds to a specific amino acid or a stop signal during protein synthesis.
