Most clinical categories were built to organize care, not to describe underlying biology. A diagnosis gives a clinician a shared vocabulary, a billing code, and a treatment protocol. That is genuinely useful. But when the category groups together people whose biology differs substantially, the category becomes a ceiling on how precisely we can reason about health.
A biotype is a biologically grounded subtype derived from measurements rather than symptom consensus. Where a diagnosis asks "which pattern of observable features does this person match," a biotype asks "what structure in biological space does this person occupy, and how does that structure relate to mechanisms and trajectories?"
Why the distinction matters for research
When researchers average across a heterogeneous diagnostic group, real signals can cancel. Two people with the same diagnosis may respond to the same intervention in opposite directions because they occupy different regions of biological space. A biotype framework makes that heterogeneity explicit rather than treating it as noise. The goal is not to replace clinical categories but to give them finer resolution where biology supports it.
Building reliable biotypes requires longitudinal data, multi-modal measurement, and careful validation across diverse populations. A biotype derived from one cohort with one data modality in one demographic group is a hypothesis, not an infrastructure component. Cytognosis treats biotype discovery as an ongoing, open process rather than a fixed taxonomy.
Biotypes and the open notebook
Because biotype definitions will evolve as evidence accumulates, we version them explicitly. Each candidate biotype in our open notebook carries its derivation conditions, the populations in which it has been evaluated, the features that define it, and the open questions that remain. This page is part of that notebook and will continue to evolve as the science does.