xGen Unique Dual Index UMI Adapters

Single-use, TA-ligation-ready, full-length adapters

xGen Unique Dual Index UMI Adapters combine the accuracy of unique dual indexing with the convenience of single-use format for a variety of sequencing applications on Illumina instruments. These full-length adapters contain 8-base unique dual indexes (UDI) that minimize read misassignment. An optional 9-base unique molecular identifier (UMI) can be used for quantitative assays or low-frequency variant detection. The adapters are methylated for bisulfite sequencing. Full-length adapters support PCR-free and PCR-amplified library preparation methods.

  • Our NGS quality control is unmatched in the industry

  • UDI is the current standard for data accuracy and confidence

  • UMIs are included for sensitive applications

  • Adapters are pre-configured and ready-to-ship

xGen Unique Dual Index UMI Adapters include P5 and P7 sequences that are compatible with Illumina sequencing platforms. These full-length NGS adapters are compatible with the Lotus DNA Library Prep Kit and other TA-ligation-based library preparation methods (Figure 1). The adapters contain a 9-base degenerate unique molecular identifier (UMI) in an optional read position. The UMI sequence can be used for quantification (counting applications like RNA-seq and ChIP-Seq) and error correction (low-frequency variant detection). The UMI is downstream of the i7 sample index, making the UMI data/information optional. This unique design provides the ability to run the adapter in 3 different schemes: single index, unique dual index, and unique molecular identifier modes.


Figure 1. xGen Unique Dual Index UMI Adapters


Sample index length 8-base non-redundant sample indexes
Number of indexes 16 unique dual indexes (UDIs) per kit
Concentration 15 µM
Shipping container 96-well plates
Reactions per well 1 (to prevent cross-contamination between indexes)
Adapter modifications Methylated for bisulfite sequencing*
QC and quantification NGS
Illumina platform compatibility 2- and 4-color platforms

* For bisulfite sequencing, see our FAQ for additional information.

Shipping and storage

  • Ships on dry ice

  • Turnaround time: typically ships within 1 business day

  • Storage temperature: –20°C

Figure 2. Uniform genome coverage for PCR-free and PCR-amplified libraries. Libraries were prepared using 100 ng of human gDNA (NA12878, Coriell) and full-length xGen Unique Dual Index UMI Adapters (IDT) with or without PCR amplification (4 cycles) and sequenced on the MiSeq® (PCR-free) and HiSeq® 4000 (amplified) platforms (Illumina). Normalized coverage of each library is shown as dark and light blue lines, the expected normalized coverage of 1.0 is indicated with a dotted line, and the number of 100 bp regions at each GC% is shown as a histogram in grey.
Figure 3. Unbiased performance for low input libraries (A) Libraries were prepared using the MSA-1000™ microbiome standard (ATTC, an artificial microbial community of 10 strains), the Lotus DNA Library Prep Kit, full-length adapters, and PCR amplified with P5 and P7 primers. (B) Libraries were prepared with 5 ng of MSA-1000 gDNA. Normalized genome coverage for 3 representative strains with varying GC% content is shown as colored lines The number of 100 bp regions at each GC% is shown as histograms.

Application notes and case studies

Index files

Data analysis guidelines

Frequently asked questions



Certificates of analysis (COAs)

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