Comprehensive evaluation of BRCA1/2 variant interpretation ability among laboratories in China

High-quality interpretation of BRCA1/2 variants plays a critical role in the clinical practice of precision medicine. However, a comprehensive system to evaluate the quality and accuracy of variant interpretation has yet to be established. This study investigates the performance of an interpretation system in evaluating the capacities of BRCA1/2 interpretation among distinct laboratories in China. The evaluation system is based on a reference database that contains 750 different variants in BRCA1/2. Evaluation was performed among 41 laboratories in China. We classified their performance into five levels. Only level A was considered qualified. This level allows for a 0.3% error rate for clinical decision-related misinterpretation; 26 of 41 laboratories (63%) met the qualified standard, while 7 laboratories were at levels D and E, which indicated egregious mistakes and systemic problems in variant interpretation. Due to strict quality demands, the interpretation of several variants was amended, which largely influenced the quality rate. The number of qualified laboratories would decrease from 26 to 17 if those incorrect recommended interpretations were not corrected. This evaluation system provides a potential approach for standardisation of variant interpretation and lowers the discordance of variant interpretation between different laboratories. A well-designed interpretation ability evaluation is essential to evaluate the interpretation level of laboratories before they provide service in real-world clinical settings.