# What is the Illumina Lysis Reagent Kit, and when should it be used?

The **Illumina Lysis Reagent Kit** (catalog number 20042221) is an optional accessory kit used to extract normalized DNA from whole fresh blood, dried blood spots, or saliva for the **Illumina DNA PCR-Free library preparation kit**. The Illumina Lysis Reagent Kit allows users to begin with raw blood or saliva samples, perform the \~1.5 hour lysis protocol, then proceed to library preparation without any quantification steps.

To use the Illumina Lysis Reagent kit, follow the lysis procedures in Appendix A of the [Illumina DNA PCR-Free Library Prep Reference Guide](https://support.illumina.com/downloads/illumina-dna-pcr-free-reference-guide.html).

**Note that this accessory kit is *****different***** than the Flex Lysis Reagent Kit** (catalog number 20018706). As a comparison, the Flex Lysis Reagent Kit is used with Illumina DNA Prep or Illumina DNA Prep with Enrichment, and is only compatible with blood, dried blood spots, and saliva samples. These kits are not interchangeable.

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| *For any feedback or questions regarding this article (Illumina Knowledge Article #5931), contact Illumina Technical Support* [*techsupport@illumina.com*](mailto:techsupport@illumina.com?subject=Question%2FFeedback%20Regarding%20Illumina%20Knowledge%20Article%20#000005931%20-%20Library%20Preparation%20\&body=Dear%20Illumina%20Technical%20Support,%0D%0A%0D%0A)*.* |


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