xGen Lockdown Probes

Individually quality controlled capture probes for targeted sequencing

xGen Lockdown Probes are individually synthesized and quality controlled 5′-biotinylated probes for hybridization capture target enrichment in next generation sequencing.

  • Achieve higher performance with individually synthesized and quality-controlled capture probes
  • Develop cost-effective custom panels that are delivered quickly
  • Optimize, expand, or combine custom panels


xGen Lockdown Probes

ScalePrice per ProbeMinimum Order
Mini (1 rxn/probe)$15.00 USD200 probes
Standard (8 rxns/probe)$25.00 USD96 probes
XL (64 rxns/probe)$35.00 USD96 probes

xGen Lockdown Probes are individually synthesized 5′-biotinylated oligos for hybridization capture enrichment in next generation sequencing. xGen Lockdown Probes are produced using the same industry-leading, high-fidelity synthesis chemistry developed for Ultramer® Oligonucleotides.

These probes can be used for creating custom capture panels that can be optimized, expanded, and combined with other panels. xGen Lockdown Probes can also be used to enhance the performance of existing capture panels, rescuing poorly represented regions such as areas of high GC content.

With xGen Lockdown Probes, you can:

  • Design probes for any sequence in any species using your specified parameters for target definition, probe length, and tiling density
  • Use for human probe targets when xGen Predesigned Gene Capture Pools do not match your criteria for design
  • Transition to high volume applications easily with 3 production scales
  • Use gene symbols, gene IDs, and BED files to identify human, mouse, and rat gene targets; the tools also accepts RefSeq accession numbers or FASTA-formatted sequences

High target coverage

Capture panels created with xGen Lockdown Probes provide deep, uniform coverage of the targeted regions (Figure 1) because all probes are present at equimolar concentrations. Individual synthesis of Lockdown Probes also delivers reliable batch-to-batch performance.

Figure 1. Consistently deep, uniform sequence coverage with xGen Lockdown Probes. A DNA library created from human genomic DNA (Coriell) was enriched for a 111 kb target region, using a capture panel created from xGen Lockdown Probes. The enriched libraries were sequenced on an Illumina NextSeq® instrument and subsampled to 2 million reads. The data show (A) deep, uniform coverage and (B) consistent median target coverage for two synthesis lots of 1,174 probes (R2 = 0.915). Coverage and target depth were calculated with Picard and BEDTools, respectively.

Improve coverage of array-synthesized baits

xGen Lockdown Probes can be added to array-derived baits to enhance the coverage of GC-rich targets, such as first exons (Figure 2).

Figure 2. Spiking in individually synthesized oligonucleotide probes improves sequencing coverage of array-derived RNA baits. Individually synthesized 5′-biotinylated Ultramer® Oligonucleotides (xGen Lockdown Probes) were spiked into commercial, array-synthesized RNA baits to improve coverage of areas with high GC content. Either (A) 1000 Ultramer oligo probes targeting a ~133 kb region, or (B) 3 Ultramer oligo probes targeting a single exon, were mixed with 1.1 Mb RNA baits and hybridized for 24 hr, followed by target capture using streptavidin. Enriched targets were sequenced on a HiSeq® 2000 system using 49 x 49 paired-end reads. Lockdown probes improved general coverage of GC-rich targets (A) and single GC-rich exons (B).

User guides and protocols

Legacy protocols

Brochures and flyers

Application notes and case studies


Frequently asked questions