GJB2 p.G4D Genomic DNA Ref Std

Product Overview

The GJB2 p.G4D Genomic DNA Ref Std is a meticulously characterized reference material designed for routine quality control of clinical genetic testing workflows targeting the p.G4D mutation in the GJB2 gene, a primary cause of hereditary hearing loss. This standard contains genomic DNA with a heterozygous p.G4D (c.10G>A) mutation at a precisely calibrated 50% mutant allele frequency, representing the genetic profile of affected individuals. Manufactured to mimic the matrix characteristics of clinical specimens, it provides a consistent reference for validating the accuracy and reproducibility of GJB2 mutation detection assays in diagnostic laboratories. With comprehensive documentation supporting regulatory compliance, this standard is an essential tool for ensuring reliable results in hearing loss genetics testing .

Product Features

Diagnostic-Grade Mutation Reference

Contains the pathogenic p.G4D mutation in heterozygous state, the most common GJB2 variant in several global populations. The mutation is verified by Sanger sequencing with >99.9% accuracy and digital droplet PCR confirming the 50% mutant allele frequency (±3% tolerance). This enables precise calibration of diagnostic thresholds for mutation calling .

Matrix Authenticity

Processed from whole blood using standard clinical extraction protocols to preserve:

• Native DNA fragmentation pattern (average 15-20 kb)

• Natural nucleosome structure

• Typical levels of cytosine methylation in the GJB2 promoter region

• Endogenous PCR inhibitors at physiological concentrations (≤0.5 ng/μL hemoglobin)

Quality Control Metrics

Each lot undergoes rigorous testing including:

• Stability testing under simulated shipping conditions

• Inter-lot variability assessment (<5% coefficient of variation)

• Compatibility testing with common clinical assay kits

• Long-term storage stability verification

Certificate of analysis includes detailed performance characteristics across multiple platforms.

Usage

Routine QC Implementation

Include in every diagnostic run as an external control at 20 ng input per reaction. Use to:

• Verify assay performance on each testing day

• Monitor technician proficiency

• Detect reagent lot-to-lot variations

• Ensure instrument calibration stability

Validation Studies

Incorporate into assay validation to demonstrate:

• Analytical sensitivity (>99% detection rate)

• Analytical specificity (>99% precision)

• Inter-run reproducibility (CV <3%)

• Robustness across acceptable input ranges (10-50 ng DNA)

Preparation Instructions

Reconstitute lyophilized DNA in 100 μL molecular biology-grade water to achieve 50 ng/μL working concentration. Allow to stand at room temperature for 15 minutes, then mix gently by inversion. Do not vortex. Store reconstituted aliquots at -20°C for up to 6 months.

FAQ

Why is GJB2 testing important for hearing loss diagnosis?

GJB2 mutations account for 20-50% of non-syndromic congenital hearing loss cases worldwide, making it the most common genetic cause. Accurate detection of mutations like p.G4D enables definitive diagnosis, recurrence risk calculation, and appropriate management including early intervention services .

How does this standard support regulatory compliance?

It meets CLIA and CAP requirements for external quality controls, providing traceable reference values with uncertainty estimates. Comprehensive documentation includes method validation data, stability studies, and performance characteristics across platforms to support regulatory submissions .

Can it be used with all GJB2 testing methods?

Yes, the standard is validated for use with all common clinical methods including allele-specific PCR, TaqMan assays, Sanger sequencing, and targeted NGS panels. Performance data for each method is provided in the certificate of analysis .

What is the shelf life under different conditions?

Unopened vials are stable at -20°C for 36 months. After reconstitution:

• -20°C storage: stable for 6 months (up to 3 freeze-thaw cycles)

• 4°C storage: stable for 30 days

• Room temperature: stable for 8 hours (≤25°C)

Technical Data

Product application

1.Evaluate the stability of the experiment and analysis process

2.Negative and negative reference/quality control products