... the same macromolecule or one that differs from the original macromolecule only with respect to changes in the molecular structure such as: ... polynucleotide substances (including gene transfer and antisense substances), consisting of two or more distinct nucleotides where:
- the difference in the nucleotide sequence of the purine and pyrimidine bases or their derivatives is not major. Therefore for antisense substances, the addition or deletion of nucleotide(s) not significantly affecting the kinetics of hybridisation to the target would normally be considered similar.
