From Laboratory Standards to Regulatory Requirements: Construction of the Quality System for Preimplantation Genetic Testing for Chromosomal Aneuploidy Kits

Core Elements of Laboratory Quality Management

Laboratories conducting preimplantation chromosomal aneuploidy detection kit testing (combined probe-anchored polymerization sequencing method) shall establish a comprehensive quality management system in accordance with the Good Manufacturing Practice for Medical Devices and the Administrative Measures for Clinical Gene Amplification Testing Laboratories. In terms of personnel, operators must hold a clinical gene amplification testing qualification certificate and receive specialized training from the kit manufacturer; equipment management shall cover regular calibration and maintenance records for sequencers, PCR instruments, centrifuges, etc.; reagent management involves receipt verification, storage temperature monitoring (typically required at -20°C or 2-8°C), and expiry management of kits; methodological validation shall include indicators such as precision, accuracy, limit of detection, and anti-interference capability. In addition, environmental control is the foundation for ensuring result reliability. Laboratories shall be divided into reagent preparation area, sample preparation area, amplification area, and sequencing area, with air pressure gradients in each area meeting positive/negative pressure requirements to avoid cross-contamination.

Regulatory Registration and Performance Evaluation Requirements

According to the National Medical Products Administration (NMPA), such kits are classified as Class III medical devices and require strict registration approval. Typical technical review requirements include: clinical studies shall be designed as prospective or retrospective double-blind controlled trials, using amniotic fluid chromosome karyotype analysis or postnatal verification results as the gold standard, with sample size meeting statistical requirements; the application materials shall clearly specify the analytical performance of the product, including accuracy (concordance rate with the gold standard not less than 95%), repeatability (intra-batch and inter-batch coefficients of variation within acceptable ranges), limit of detection (e.g., minimum detectable DNA amount from 1-5 cells), and interference validation (e.g., effects of maternal cell contamination, hemolysis, lipemia, and other interfering substances). After approval and marketing, enterprises shall also fulfill obligations for adverse event monitoring, re-evaluation, and renewal registration. In recent years, regulatory authorities have imposed increasingly stringent requirements on bioinformatics software, requiring detailed descriptions and validation reports for data analysis algorithms, reference databases, and result interpretation rules.

External Quality Assessment and Continuous Improvement

To ensure consistency and mutual recognition of test results among different laboratories, laboratories shall regularly participate in chromosomal aneuploidy detection external quality assessment programs organized by the National Center for Clinical Laboratories of the National Health Commission or provincial clinical testing centers. Quality assessment samples typically include different karyotypes (such as 46,XX, 47,XY,+21, 45,X, etc.) as well as mosaic samples. Laboratories shall submit test results within a specified time limit and evaluate their concordance with expected results. For nonconforming items, root cause analysis shall be initiated and corrective and preventive actions taken. In addition, laboratories shall establish an internal sample tracking system to record the entire process of receipt, processing, sequencing, and reporting of each test sample, while retaining quality control charts for negative and positive controls to facilitate trend analysis. If a kit undergoes version updates or process changes, the laboratory shall re-perform method comparison to ensure consistency of results between the old and new systems.

Ethical Considerations and Result Consultation Services

The application of detection kits also involves complex ethical and counseling aspects. Medical institutions must be equipped with experienced genetic counselors to fully explain to patients before testing the applicable scope, limitations (such as inability to detect polyploidy, uniparental disomy, low-level mosaicism, etc.), and possible false positive/false negative risks of the technology. After testing, the clinical report shall include clear chromosomal copy number variation results and recommend the necessity of subsequent prenatal diagnostic verification (such as amniocentesis). At the same time, laboratories shall establish a strict privacy protection system, with test data used only for clinical diagnostic purposes and not arbitrarily used for other research. In addition, it is recommended to establish a multidisciplinary consultation mechanism, with experts in reproductive medicine, genetics, prenatal diagnosis, and ethics jointly evaluating complex cases, such as those involving multiple chromosomal abnormalities or rare structural rearrangements, to ensure that patients receive scientific and prudent medical advice.