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IMGT numbering of additional codons (or amino acids) and corresponding nucleotides

Additional codons (or amino acids) and corresponding nucleotides are identified by a number (the one of a neighbour reference codon) followed by a dot and number, or by a letter:

a dot and number, for expected additional codons (or amino acids)

a capital letter, for unusual insertions (or insertions that need to be underlined)


Examples:

Note that