Science, Tech, Math › Science Table of mRNA Codons and Properties of the Genetic Code Learn About the Genetic Code Share Flipboard Email Print ALFRED PASIEKA/SCIENCE PHOTO LIBRARY/Getty Images Science Chemistry Biochemistry Basics Chemical Laws Molecules Periodic Table Projects & Experiments Scientific Method Physical Chemistry Medical Chemistry Chemistry In Everyday Life Famous Chemists Activities for Kids Abbreviations & Acronyms Biology Physics Geology Astronomy Weather & Climate By Anne Marie Helmenstine, Ph.D. Anne Marie Helmenstine, Ph.D. Facebook Twitter Chemistry Expert Ph.D., Biomedical Sciences, University of Tennessee at Knoxville B.A., Physics and Mathematics, Hastings College Dr. Helmenstine holds a Ph.D. in biomedical sciences and is a science writer, educator, and consultant. She has taught science courses at the high school, college, and graduate levels. Learn about our Editorial Process Updated on January 26, 2019 This is a table of mRNA codons for the amino acids and a description of the properties of the genetic code. Genetic Code Properties There is no ambiguity in the genetic code. This means each triplet codes for only one amino acid. The genetic code is degenerate, which means there is more than one triplet code for many of the amino acids. Methionine and tryptophan each are coded by just one triplet. Arginine, leucine, and serine each are coded by six triplets. The other 15 amino acids are coded by two, three, and four triplets. There are 61 triplet codes for amino acids. Three other triplets (UAA, UAG, and UGA) are stop sequences. The stop sequences signal chain termination, telling the cellular machinery to stop synthesizing a protein. The degeneracy of the code for the amino acids coded by two, three, and four triplets is only in the last base of the triplet code. As an example, glycine is coded by GGU, GGA, GGG, and GGC. Experimental evidence indicates the genetic code is universal for all organisms on Earth. Viruses, bacteria, plants, and animals all use the same genetic code to form proteins from RNA. Table of mRNA Codons and Amino Acids mRNA Amino Acid mRNA Amino Acid mRNA Amino Acid mRNA Amino Acid UUU Phe UCU Ser UAU Tyr UGU Cys UUC Phe UCC Ser UAC Tyr UGC Cys UUA Leu UCA Ser UAA Stop UGA Stop UUG Leu UCG Ser UAG Stop UGG Trp --- --- --- --- --- --- --- --- CUU Leu CCU Pro CAU His CGU Arg CUC Leu CCC Pro CAC His CGC Arg CUA Leu CCA Pro CAA Gln CGA Arg CUG Leu CCG Pro CAG Gln CGG Arg --- --- --- --- --- --- --- --- AUU Ile ACU Thr AAU Asn AGU Ser AUC Ile ACC Thr AAC Asn AGC Ser AUA Ile ACA Thr AAA Lys AGA Arg AUG Met ACG Thr AAG Lys AGG Arg --- --- --- --- --- --- --- --- GUU Val GCU Ala GAU Asp GGU Gly GUC Val GCC Ala GAC Asp GGC Gly GUA Val GCA Ala GAA Glu GGA Gly GUG Val GCG Ala GAG Glu GGG Gly Cite this Article Format mla apa chicago Your Citation Helmenstine, Anne Marie, Ph.D. "Table of mRNA Codons and Properties of the Genetic Code." ThoughtCo, Aug. 26, 2020, thoughtco.com/table-of-mrna-codons-genetic-code-603871. Helmenstine, Anne Marie, Ph.D. (2020, August 26). Table of mRNA Codons and Properties of the Genetic Code. Retrieved from https://www.thoughtco.com/table-of-mrna-codons-genetic-code-603871 Helmenstine, Anne Marie, Ph.D. "Table of mRNA Codons and Properties of the Genetic Code." ThoughtCo. https://www.thoughtco.com/table-of-mrna-codons-genetic-code-603871 (accessed June 4, 2023). copy citation By clicking “Accept All Cookies”, you agree to the storing of cookies on your device to enhance site navigation, analyze site usage, and assist in our marketing efforts. Cookies Settings Accept All Cookies