Guidelines for Sample Preparation for Infinium Genotyping Assay DNA input

Infinium Assay Sample Input Guidelines

Sample input guidelines:

Infinium Assay Format

DNA input amount

DNA input volume

DNA input concentration

Applicable step(s)

HD, HTS, LCG, XT

200 ng

4 μl

50 ng/μl

Amplify WGA

LCG Quad

400 ng

8 μl

50 ng/μl

Amplify WGA

GDA + ePGx

* 100 ng for WGA plate

  • 100 ng for PGx plate

(200 ng total) | 5 μl each | 20 ng/μl | * Amplify WGA

  • Amplify PGx | | Infinium EX | 100 ng | 5 μl | 20 ng/μl | Make WGA | | Infinium EX PGx | * 100 ng for WGA plate

  • 100 ng for PGx plate

(200 ng total) | 5 μl each | 20 ng/μl | * Make WGA

  • Make PGx |

Any standard DNA extraction method or kit that provides high quality genomic DNA is suitable for Infinium Arrays.

DNA quantity* Determine DNA concentration using a double stranded DNA specific fluorometric method (eg, Qubit, Quant-it, PicoGreen) for accurate measurement of double-stranded DNA.

  • DNA quantification results from UV spectrophotometric methods do not accurately reflect the concentration of double-stranded DNA and are not recommended.

  • Using the quantification values from the Bioanalyzer or Tapestation is not advised.

DNA quality* The minimum recommended fragment size is 2 kb.

  • Illumina does not provide DNA integrity (DIN) guidelines or cut-offs for DNA input into the Infinium assay. DIN values from a Tapestation or BioAnalyzer can be used to assess DNA quality, but are not required.

  • The presence of RNA in samples does not interfere with the Infinium assay.

  • UV spectrophotometry can be used to assess DNA purity and quality. Consider standard purity specifications:

    1. Protein/RNA free: 260/280 ratio >1.85

    2. Solvent free: 260/230 ratio >2.0

    3. Phenol free: no peak at 270 nm

Recommendations for processing low quality DNA in the Infinium Assay

  • The Infinium FFPE QC Kit:

  • Uses a real-time PCR assay to evaluate the quality of prospective DNA samples.

  • Determines whether the DNA samples are suitable for the restoration step.

  • Is only compatible with human samples.

  • The Infinium HD FFPE DNA Restore Kit:

    • Restores degraded DNA to an amplifiable state that can be used as input for the Infinium assay.

    • Is compatible with samples from any species.

Knowledge Base articles:

Last updated

Was this helpful?