Why genetic code is comma-less?

Answer 1

When a gene is translated into a polypeptide, the codons (each made up of three sequential bases) are sequential on the mRNA. There are no extra bases between the codons, every base in the open reading frame is part of exactly one codon. Furthermore, every possible codon (all 64 three base combinations of the four bases) codes for either an amino acid, or a "stop", so there are no meaningless codons.

If the code had "commas" that would mean that there could be bases between codons, or that some triplets would not code for any amino acid (or "stop"). In the 1960's, when researchers were first investigating the nature of the genetic code, the presence of commas in the code seemed like a reasonable hypothesis, particularly once it was established that the code was a triplet code, which means that there are many more possible codons than amino acids (64 vs 20).

Answer 2

The genetic code is comma-less because each group of three nucleotides (called a codon) on the mRNA strand represents a single amino acid in the protein sequence. There are no spaces between codons, so the code is read continuously without interruptions. This lack of commas or other punctuation allows for efficient and accurate translation of the genetic information into proteins.