The ABri and ADan peptides are extensions of the normal C terminus of ITM2B (BRI). The sequence of ABri results from mutatin of the normal stop codon to R, resulting in an additional 11 residues. The ABri peptide is the last 34 residues of this mutated peptide - EASNCFAIRHFENKFAVETLICSRTVKKNIIEEN.
The ADan peptide is the result of a 10 nucleotide insertion between the codons for residue 265 and 266, introducing a frameshift that adds a different extension to the normal peptide. The ADan peptide is the last 34 residues of this mutated peptide, identical to ABri for the first 22 residues.