Exogenous spikes
Contraints:
- Must not: be expressed in same species
- Must: include cDNA probe on array
- Must: add in-vitro transcribed spike to sample
- Must: estimate amount of total RNA in sample
Rewards:
- Irons out variations from labelling to quantification
- Absolute measures (no #DIV/0!…)
- Cross platform/experiment comparisons (theoretical…)
- Works with low density arrays (thematic sets, clinical etc.)