What do 'sequence' and 'analogue' mean when people talk about a peptide?
Updated: 2026-09-09 · Basics
Short answer
The sequence is the order of amino acids that defines the peptide; change it and you change the molecule. A native peptide is the one the body makes. An analogue is a deliberately modified version, usually to last longer or bind better to its receptor. Native and analogue do not behave the same.
In plain English
- A single amino acid change can alter stability, binding and how long it lasts in the body.
- Many peptide medicines are analogues, not the original human molecule.
- Adding fatty chains or modifying the ends are common design strategies.
- Evidence for one analogue does not automatically transfer to the native peptide, or the reverse.
What we know
- Analogues are designed to change pharmacokinetic or binding properties.
- The exact sequence is what identity testing checks for.
What we don't know yet
- Predicting every effect of a modification before studying it is not possible.
- For many lightly studied analogues there is no comparative human data.