Hereditary Genetic EQA Control

Definition

Hereditary Genetic: Refers to specific gene loci or variants associated with genetic diseases.

Interlaboratory Controls: "Interlaboratory" refers to the use between different laboratories; "controls" are samples used for quality control. These are samples with known, accurate results that are distributed to multiple laboratories for testing to assess and compare the accuracy and consistency of test results across different laboratories.

Thus, the definition of a Hereditary Genetic control is:

A standard material or sample containing a known, defined genotype (such as a specific point mutation, insertion/deletion, or gene copy number variation) distributed to different laboratories performing genetic testing to monitor and evaluate the accuracy, reliability, and comparability of the laboratory's testing process.

The Role of Hereditary Genetic EQA Control

Their core role is to ensure the quality of genetic testing, as demonstrated in the following aspects:

*Assessing Test Accuracy: The "standard answer" (known genotype) provided by the control can be compared with the laboratory's "test answer." Any discrepancies in the results may indicate a problem with the laboratory's testing process.

*Ensuring interlaboratory comparability: Ideally, different laboratories using different instruments, reagents, and methods to test the same quality control material should produce identical results. This is the foundation for achieving "testing in one hospital, being recognized in another" and is crucial for patient referrals and remote consultations.

*Monitoring the entire testing process: Errors can occur at every stage, from sample nucleic acid extraction, library preparation, sequencing (or PCR amplification), to data analysis. Quality control materials can help identify the cause of problems.

*Validating new methods and technologies: When laboratories introduce new testing technologies or reagents, quality control materials can be used to verify that the performance and reliability of the new methods meet standards.

*Meeting accreditation and regulatory requirements: Almost all laboratory accreditation schemes (such as CAP, CLIA, and ISO15189) require laboratories to regularly participate in external quality assessment activities, and the use of standard quality control materials is essential for participating in these activities.

Disease-Related

Genetic genetic external quality control materials are relevant to all genetic diseases that require genetic testing for diagnosis, prognosis, or screening. Whenever a disease has a clear causative gene or related genes, corresponding quality control products are required to ensure test quality. 

Common examples include:

*Hereditary tumors: such as breast and ovarian cancer (BRCA1/2 genes), Lynch syndrome (MLH1, MSH2, MSH6, PMS2 genes), and familial adenomatous polyposis (APC gene).

*Hereditary cardiovascular diseases: such as genes associated with hypertrophic cardiomyopathy, long QT syndrome, and familial hypercholesterolemia.

*Hereditary neurological diseases: such as Huntington's disease, hereditary spastic paraplegia, and Duchenne/Berkshire muscular dystrophy (DMD gene).

*Hereditary metabolic diseases: such as phenylketonuria, thalassemia, and hemophilia.

*Prenatal screening and diagnosis: Quality control products used in non-invasive prenatal genetic testing (NIPT) for chromosomal aneuploidies such as Down syndrome.

*Pharmacogenomics: Detects genetic polymorphisms related to drug metabolism and efficacy (such as CYP2C19, CYP2C9, and VKORC1) to enable personalized medication.

In short, any genetic disease requiring genetic testing requires corresponding genetic external quality control products to ensure safety.

Application Scenarios

Genetic external quality control products are primarily used in the following scenarios:

1.Internal laboratory quality control

Laboratories regularly use quality control products to run testing processes, monitor the stability of their own testing status, and ensure that every report issued is accurate and reliable.

2.External quality evaluation plan

①Authoritative organizations (such as the National Health Commission's Clinical Inspection Center, provincial clinical inspection centers, and CAP) distribute the same batch of quality control products to hundreds or even thousands of participating laboratories.

②Laboratories complete the testing and report the results within a specified timeframe.

③The organizers collect all results, conduct statistical analysis, and publish an evaluation report. This report allows laboratories to understand their performance relative to other participating laboratories and identify and correct any deficiencies.

3.Validation of New Test Items or Platforms

When a laboratory launches a new genetic test or purchases a new sequencer/PCR instrument, it must use quality control products with known results to verify that the accuracy and precision of the new test item or platform meet clinical testing requirements.

4.Development and Quality Control by Kit and Instrument Manufacturers

When developing new test kits or instruments, manufacturers need to use standard quality control products to evaluate and demonstrate their product performance.

Quality control products are also used during batch quality testing on the production line to ensure consistent quality across kit batches.

5.Laboratory Accreditation and Review:

During on-site laboratory reviews, reviewers will review the laboratory's records and results from external quality assessments, as well as the use of quality control products in internal quality control. These records serve as a critical indicator of the laboratory's technical capabilities.

Summary: Genetic external quality control products serve as the "yardstick" and "examiner" of genetic testing. It assesses and supervises the testing capabilities of each laboratory by providing known standard answers, ensuring that genetic testing results obtained at different times, locations and methods are accurate, reliable and comparable, ultimately safeguarding the safety of patient diagnosis and treatment and the healthy development of the medical testing industry.