DNA codon table

The standard genetic code is traditionally represented as an RNA codon table because, when proteins are made in a cell by ribosomes, it is mRNA that directs protein synthesis. The mRNA sequence is determined by the sequence of genomic DNA. With the rise of computational biology and genomics, most genes are now discovered at the DNA level, so a DNA codon table is becoming increasingly useful.[1] In this context, the standard genetic code is referred to as translation table 1.[2]

The DNA codons in such tables occur on the sense DNA strand and are arranged in a 5' → 3' direction. There is the existence of symmetrical and asymmetrical characteristics in genetic codes.[3]

Amino-acid biochemical properties Nonpolar Polar Basic Acidic Termination: stop codon
Standard genetic code
1st
base		 2nd base 3rd
base
T C A G
T TTT (Phe/F) Phenylalanine TCT (Ser/S) Serine TAT (Tyr/Y) Tyrosine TGT (Cys/C) Cysteine T
TTC TCC TAC TGC C
TTA (Leu/L) Leucine TCA TAA Stop (Ochre)[B] TGA Stop (Opal)[B] A
TTG[A] TCG TAG Stop (Amber)[B] TGG (Trp/W) Tryptophan G
C CTT CCT (Pro/P) Proline CAT (His/H) Histidine CGT (Arg/R) Arginine T
CTC CCC CAC CGC C
CTA CCA CAA (Gln/Q) Glutamine CGA A
CTG[A] CCG CAG CGG G
A ATT (Ile/I) Isoleucine ACT (Thr/T) Threonine AAT (Asn/N) Asparagine AGT (Ser/S) Serine T
ATC ACC AAC AGC C
ATA ACA AAA (Lys/K) Lysine AGA (Arg/R) Arginine A
ATG[A] (Met/M) Methionine ACG AAG AGG G
G GTT (Val/V) Valine GCT (Ala/A) Alanine GAT (Asp/D) Aspartic acid GGT (Gly/G) Glycine T
GTC GCC GAC GGC C
GTA GCA GAA (Glu/E) Glutamic acid GGA A
GTG GCG GAG GGG G
A The codon ATG both codes for methionine and serves as an initiation site: the first ATG in an mRNA's coding region is where translation into protein begins.[4] The other start codons listed by GenBank are rare in eukaryotes and generally codes for Met/fMet.[5]
B ^ ^ ^ The historical basis for designating the stop codons as amber, ochre and opal is described in an autobiography by Sydney Brenner[6] and in a historical article by Bob Edgar.[7]
Inverse table for the standard genetic code (compressed using IUPAC notation)
Amino acidDNA codonsCompressed Amino acidDNA codonsCompressed
Ala, A GCT, GCC, GCA, GCG GCN Ile, I ATT, ATC, ATA ATH
Arg, R CGT, CGC, CGA, CGG; AGA, AGG CGN, AGR; or
CGY, MGR		 Leu, L CTT, CTC, CTA, CTG; TTA, TTG CTN, TTR; or
CTY, YTR
Asn, N AAT, AAC AAY Lys, K AAA, AAG AAR
Asp, D GAT, GAC GAY Met, M ATG
Asn or Asp, B AAT, AAC; GAT, GAC RAY Phe, F TTT, TTC TTY
Cys, C TGT, TGC TGY Pro, P CCT, CCC, CCA, CCG CCN
Gln, Q CAA, CAG CAR Ser, S TCT, TCC, TCA, TCG; AGT, AGC TCN, AGY
Glu, E GAA, GAG GAR Thr, T ACT, ACC, ACA, ACG ACN
Gln or Glu, Z CAA, CAG; GAA, GAG SAR Trp, W TGG
Gly, G GGT, GGC, GGA, GGG GGN Tyr, Y TAT, TAC TAY
His, H CAT, CAC CAY Val, V GTT, GTC, GTA, GTG GTN
START ATG STOP TAA, TGA, TAG TRA, TAR

See also

References
  1. Kimball, John (2014-05-01). "The Genetic Code". Kimball's Biology Pages. Archived from the original on 2016-12-22. Retrieved 2015-08-15.
  2. Elzanowski, Andrzej; Ostell, Jim (7 January 2019). "The Genetic Codes (National Center for Biotechnology Information: NCBI)". Retrieved 21 February 2019.
  3. Shu, Jian-Jun (2017). "A new integrated symmetrical table for genetic codes". BioSystems. 151: 21–26. arXiv:1703.03787. doi:10.1016/j.biosystems.2016.11.004. PMID 27887904.
  4. Nakamoto T (March 2009). "Evolution and the universality of the mechanism of initiation of protein synthesis". Gene. 432 (1–2): 1–6. doi:10.1016/j.gene.2008.11.001. PMID 19056476.
  5. Blattner, F. R.; Plunkett g, G.; Bloch, C. A.; Perna, N. T.; Burland, V.; Riley, M.; Collado-Vides, J.; Glasner, J. D.; Rode, C. K.; Mayhew, G. F.; Gregor, J.; Davis, N. W.; Kirkpatrick, H. A.; Goeden, M. A.; Rose, D. J.; Mau, B.; Shao, Y. (1997). "The Complete Genome Sequence of Escherichia coli K-12". Science. 277 (5331): 1453–1462. doi:10.1126/science.277.5331.1453. PMID 9278503.
  6. Brenner S. A Life in Science (2001) Published by Biomed Central Limited ISBN 0-9540278-0-9 see pages 101-104
  7. Edgar B (2004). "The genome of bacteriophage T4: an archeological dig". Genetics. 168 (2): 575–82. PMC 1448817. PMID 15514035. see pages 580-581
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