Nucleotide ambiguity code as defined in DNA Sequence Assembler.
| Symbol | Description | Bases represented | Complement | 
|---|---|---|---|
| A | Adenine | A – – – | V | 
| C | Cytosine | – C – – | H | 
| G | Guanine | – – G – | D | 
| T | Thymine | – – – T | B | 
| W | Weak | A – – T | S | 
| S | Strong | – C G – | W | 
| M | aMino | A C – – | K | 
| K | Keto | – – G T | M | 
| R | puRine | A – G – | Y | 
| Y | pYrimidine | – C – T | R | 
| B | not A | – C G T | A | 
| D | not C | A – G T | C | 
| H | not G | A C – T | G | 
| V | not T | A C G – | T | 
| N | any Nucleotide | A C G T | Z | 
| Z | Zero | – – – – | N | 
The standard ambiguity codes for nucleotides and for the one-letter and three-letter designations of amino acids. Notice that all the entries in the same row encodes to the corresponding amino acid.
| Amino Acid (full) | 3-Let | 1-Let | Codons (triplets) | Compressed (compact) | 
|---|---|---|---|---|
| Alanine | Ala | A | GCT, GCC, GCA, GCG | GCN | 
| Cysteine | Cys | C | TGT, TGC | TGY | 
| Aspartic | Asp | D | GAT, GAC | GAY | 
| Glutamic | Glu | E | GAA, GAG | GAR | 
| Phenylalanine | Phe | F | TTT, TTC | TTY | 
| Glycine | Gly | G | GGT, GGC, GGA, GGG | GGN | 
| Histidine | His | H | CAT, CAC | CAY | 
| Isoleucine | Ile | I | ATT, ATC, ATA | ATH | 
| Lysine | Lys | K | AAA, AAG | AAR | 
| Leucine | Leu | L | TTA, TTG, CTT, CTC, CTA, CTG | YTR, CTN | 
| Methionine | Met | M | ATG | |
| Asparagine | Asn | N | AAT, AAC | AAY | 
| Proline | Pro | P | CCT, CCC, CCA, CCG | CCN | 
| Glutamine | Gln | Q | CAA, CAG | CAR | 
| Arginine | Arg | R | CGT, CGC, CGA, CGG, AGA, AGG | CGN, MGR | 
| Serine | Ser | S | TCT, TCC, TCA, TCG, AGT, AGC | TCN, AGY | 
| Threonine | Thr | T | ACT, ACC, ACA, ACG | ACN | 
| Valine | Val | V | GTT, GTC, GTA, GTG | GTN | 
| Tryptophan | Trp | W | TGG | |
| Tyrosine | Tyr | Y | TAT, TAC | TAY |