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Ambiguity codes

Ambiquity codes are codes that mean any of the two or any of the three nucleotides. Normally, purine (R, A or G) is complemented into pyrimidine (Y, C or T) and amino (M, C or A) is complemented into keto (K, T or G). Differently, weak (W, A or T, pairs with the two hydrogen bonds) and strong (S, G or C, pairs with three hydrogen bonds) are normally not swapped during complementation, leaving the S and W codes unchanged instead. This is logical as both a nucleotide and its complement use the same number of bonds to make a complementing pair. See this, for instance. Here is the complete table of our converter:

CodeNucleotidesComplement
AAT
GGC
CCG
TTA
UUA
RA or G, purineY, pyrimidine
YC or T, pyrimidineR, purine
SC or G, strong pairingS, unchanged
WA or T, weak pairingW, unchanged
KG or T, ketoM, amino
MA or C, aminoK, keto
BC or G or T, not AV, not T
VA or C or G, not TB, not A
DA or G or T, not CH, not G
HA or C or T, not GD, not C
-gapunchanged
any otherany or unknownunchanged

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