Individual blocking oligos

Reduce off-target capture by preventing adapter cross hybridization with xGen® Blocking Oligos.

xGen Blocking Oligos bind to adapter sequences to help prevent non-specific binding. Blocking the adapter sequences significantly improves capture performance. All xGen blocking oligos are compatible with any xGen Lockdown® Panel or custom xGen Lockdown Probe set. Various blocking oligo options are available to accommodate different requirements and sequencing platforms. Choose from:

  • xGen Standard Blocking Oligos
  • xGen Blocking Oligos for Ion Torrent adapters

IDT recommends xGen Universal Blockers for Illumina TruSeq® and Nextera™ indexed libraries.


xGen Standard Blocking Oligos

For single-index adapters (e.g., Illumina TruSeq®)

Predesigned to bind to the most common single-index library adapters that comprise 1 universal adapter and 24 barcoded adapters. The 24 blocking oligos for the barcoded adapters are labeled 1–27, corresponding to the numbering scheme used in Illumina, NEB, and Bioo Scientific single-index adapter kits.

For dual-index adapters (e.g., Illumina TruSeq HT)

Designed to block Illumina TruSeq HT dual-index adapters, i5 and i7. The i5 oligos consist of numbers D501–D508 and the i7 oligos consist of D701–D712.

For Ion Torrent® barcoded adapters

Predesigned against 2 non-barcoded adapters (A and P1) and 32 barcoded A adapters.

xGen Universal Blocking Oligos for Ion Torrent platforms

User guides and protocols

Brochures and flyers