Genetic Code: A short Guide

The genetic code is the one that defines the rules according to which several genetic information can be obtained.

The system includes the mapping of tri-nucleotide sequence known as codons and amino acid. Each nucleotides triplet in the nucleic acid sequence signifies one amino acid.

Some genes are encoded with similar code. The genetic code, in particular, is known to be the canonical/standard genetic code or only, genetic code. There are many varieties of systems, and the canonical genetic code is not a universal one.

In the case of humans, the protein synthesis in mitochondria depends on the genetic code, which varies a lot from the canonical system. The genome of the organism is marked in DNA/RNA.

Gene is the part of the genome that codes the protein or the RNA.

Genes that codes the protein is made of tri-nucleotide units, which are known as codons. Each of the codings is for one amino acid. The main ingredient of every sub nucleotide unit includes the following -

  • Deoxyribose sugar
  • Phosphate
  • Any one of the four nitrogenous nucleotide bases

The purine bases (Adenine - A and guanine - G) are comprised of two aromatic rings. The pyrimidine bases (cytosine – C and thymine – T) are composed of only one aromatic ring and are quite smaller.

The two strands of DNA are connected regarding double-helix configuration. They are linked to each other by hydrogen bonds according to the base pairing procedure.

These type of bonds often form in between the adenine and thymine base (one strand of each base). Also between guanine base and cytosine base (one strand from each base).

At the given double helix, the number of A and T residue will be the same. It is the same case as the numbers of G and C residues. Thymine (T) and uracil (U) and deoxyribose are replaced by ribose in RNA.