Question: Why do I see an increased High Molecular Weight (HMW) peak at 2000bp in the Multiome ATAC library trace?
Answer: In Multiome ATAC final libraries, you may notice an increase in the HMW peak at 2000 bp compared to what we normally see in the standalone ATAC assays. This HMW peak is normal and in our in-house tests, we do not see a significant difference between the peaks, fragment distribution, and cell-type annotation when we sequenced such libraries with an increased HMW peak. When you sequence Multiome ATAC libraries, the nucleosome-free and mono-nucleosome fragments will comprise most of the sequences as the HMW peak will not cluster well on the flow cell.
Products: Single Cell Multiome ATAC + GEX