> For the complete documentation index, see [llms.txt](https://knowledge.illumina.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://knowledge.illumina.com/library-preparation/multiomics-library-prep/library-preparation-multiomics-library-prep-faq-list/000009942.md).

# UMI and index FAQ for the Illumina 5 Base Whole Genome Sequencing (WGS) and Enrichment kits

**What indexes do these library prep kits require?**

Both the WGS and Enrichment kits required the Illumina DNA/RNA UD Indexes (v3):

* Set A: 20091654
* Set B: 20091656
* Set C: 20091658
* Set D: 20091660
* Set LT: 20098166

**Where are the sequences of the Illumina DNA/RNA UDI indexes listed?**

* Sequences can be found in the Adapter Sequences Document, [here](https://support-docs.illumina.com/SHARE/AdapterSequences/Content/Illumina-UDIndexes.htm).

**Does the prep include unique molecular identifiers (UMIs)?**

* Yes, the prep includes both unique molecular identifiers (UMIs) and unique dual indexes (UDIs). The UMIs are their own reagent (a single tube) included in the library prep reagents, while the UDIs are provided in a plate and sold separately. The UMIs will require override cycles in BaseSpace Sequence Hub (BSSH).

**Where in the library are the UMIs?**

* UMIs are at the start of Read1 and Read2.

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| *For any feedback or questions regarding this article (Illumina Knowledge Article #9942), contact Illumina Technical Support* [*techsupport@illumina.com*](mailto:techsupport@illumina.com?subject=Question%2FFeedback%20Regarding%20Illumina%20Knowledge%20Article%20#000009942%20-%20Library%20Preparation%20\&body=Dear%20Illumina%20Technical%20Support,%0D%0A%0D%0A)*.* |


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