单核苷酸变异是基因组中最常检测到的序列变化类型，而其中大部分是意义未明的变异。意义未明的变异是指对疾病风险关联尚未确定的DNA变化。因此，可以利用对变异功能影响进行分类的方法作为解读变异的证据。关于乳腺和卵巢癌特异性抑癌蛋白BRCA1而言，致病性错义变异在DNA双链断裂的同源重组修复（homology-directed repair，HDR）反应中通常得分为功能丧失。我们之前使用多重化的试验在BRCA1蛋白氨基末端的第2-192个残基位置上发表了功能结果。本研究中，我们采用了改进的分析流程对该多重化试验的数据进行了重新评估。这些新的分析方法可以为BRCA1的前192个氨基酸亚残基提供功能得分，并且我们还报告了BRCA1的氨基酸残基193-302的新结果。我们现在展示了使用多重化HDR试验对BRCA1在残基2-302的2172个变异进行的功能分类。将错义变异的功能判定与临床已知的良性或致病性变异进行比较，该试验的敏感性为93%，特异性为100%。在这个试验中测试的BRCA1变异结果是临床遗传学家评估BRCA1中意义未明变异的证据资源。版权：这是一篇开放获取的文章，无版权限制，任何人可以自由复制、分发、传输、修改、建立衍生作品或以任何合法目的使用。该作品在Creative Commons CC0公共领域奉献下提供。

Single nucleotide variants are the most frequent type of sequence changes detected in the genome and these are frequently variants of uncertain significance (VUS). VUS are changes in DNA for which disease risk association is unknown. Thus, methods that classify the functional impact of a VUS can be used as evidence for variant interpretation. In the case of the breast and ovarian cancer specific tumor suppressor protein, BRCA1, pathogenic missense variants frequently score as loss of function in an assay for homology-directed repair (HDR) of DNA double-strand breaks. We previously published functional results using a multiplexed assay for 1056 amino acid substitutions residues 2-192 in the amino terminus of BRCA1. In this study, we have re-assessed the data from this multiplexed assay using an improved analysis pipeline. These new analysis methods yield functional scores for more variants in the first 192 amino acids of BRCA1, plus we report new results for BRCA1 amino acid residues 193-302. We now present the functional classification of 2172 BRCA1 variants in BRCA1 residues 2-302 using the multiplexed HDR assay. Comparison of the functional determinations of the missense variants with clinically known benign or pathogenic variants indicated 93% sensitivity and 100% specificity for this assay. The results from BRCA1 variants tested in this assay are a resource for clinical geneticists for evidence to evaluate VUS in BRCA1.Copyright: This is an open access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.