Question: Why does Visium for FFPE call for DV200 as opposed to RIN evaluation for sample quality assessment?
Answer: It has been found that the RNA Integrity Number (RIN) is not a sensitive measure of RNA quality for FFPE samples. Instead, mean FFPE RNA fragment size has been found to be a more reliable determinant of RNA quality. This requires a measurement of the percentage of total RNA fragments >200 nucleotides (DV200) for RNA quality assessment upstream of library preparation.
We have found that DV200 of ≥50% is a good predictor for generating successful Visium for FFPE Spatial Gene Expression libraries. Details on how to perform RNA Quality Assessment are in our Tissue Preparation Guide.
Products: Visium for FFPE