Genomic DNA tTMB-P9 Standard for NGS QC

Product Overview

The Genomic DNA tTMB-P9 Standard for NGS QC is a meticulously characterized reference material designed specifically for quality control of tissue-based tumor mutational burden (tTMB) assays in clinical next-generation sequencing workflows. This standard derives from well-characterized cell lines with a validated 9th percentile tTMB value (tTMB-P9), representing the low-TMB phenotype critical for establishing assay specificity and dynamic range. Manufactured to mimic the genomic complexity of clinical tumor specimens, it provides a consistent reference for monitoring NGS performance in oncology laboratories focused on immunotherapy eligibility testing .

Product Features

Clinically Defined TMB Baseline

The standard exhibits a validated tTMB value at the 9th percentile of clinical tumor specimens (3.2 mutations/Mb), verified by >300x NGS coverage across 500+ cancer-related genes. This establishes a critical baseline for distinguishing low-TMB from high-TMB samples in clinical practice .

Genome-Wide Mutational Distribution

Unlike targeted controls, this standard contains a genome-wide distribution of mutations with >95% concordance to low-TMB tumor profiles observed in The Cancer Genome Atlas (TCGA) database. Mutation types include synonymous, non-synonymous, and splice-site variants in proportions matching clinical specimens .

QC Monitoring Capabilities

Incorporates 20 spike-in control mutations at known allelic frequencies (0.5-5%) to enable simultaneous validation of:

• Variant calling accuracy across mutation types

• Coverage uniformity across genomic regions

• PCR bias correction efficiency

• Bioinformatics pipeline performance

Usage

Assay Calibration

Use at a standard input of 50 ng per reaction to establish baseline performance metrics. Run in parallel with high-TMB controls to verify assay dynamic range. Include in every NGS run as a negative control for high-TMB classification.

Quality Control Implementation

Integrate into laboratory QC protocols to:

• Monitor reagent lot-to-lot variability

• Verify technician proficiency in tTMB analysis

• Validate instrument maintenance effects on results

• Ensure compliance with CAP/CLIA requirements for assay verification

Preparation Instructions

Reconstitute lyophilized DNA in 100 μL TE buffer (pH 8.0) to achieve a working concentration of 50 ng/μL. Allow to rehydrate at room temperature for 30 minutes with gentle mixing. Avoid vortexing to prevent DNA shearing .

FAQ

What is the significance of the 9th percentile TMB value?

The 9th percentile represents the clinical threshold for low TMB, below which tumors are typically less responsive to immune checkpoint inhibitors. This standard enables laboratories to validate their ability to reliably identify this clinically important subgroup .

How does this standard differ from tTMB standards with higher values?

While high-TMB standards validate sensitivity, this tTMB-P9 standard focuses on specificity—ensuring assays do not falsely classify low-TMB tumors as high-TMB, which could lead to inappropriate immunotherapy administration .

Is it compatible with all NGS platforms?

Yes, the standard is validated for use with Illumina NovaSeq, MiSeq, and Ion Torrent Genexus platforms. Performance characteristics are provided for each platform in the certificate of analysis .

What is the shelf life after reconstitution?

Reconstituted DNA remains stable for up to 30 days when stored at 4°C in aliquots. For longer storage, freeze at -20°C for up to 6 months. Avoid more than 3 freeze-thaw cycles to maintain integrity .