Abstract：
UNASSIGNED: Brugada syndrome is an inheritable arrhythmia condition that is associated with rare, loss-of-function variants in SCN5A. Interpreting the pathogenicity of SCN5A missense variants is challenging, and ≈79% of SCN5A missense variants in ClinVar are currently classified as variants of uncertain significance. Automated patch clamp technology enables high-throughput functional studies of ion channel variants and can provide evidence for variant reclassification.
UNASSIGNED: An in vitro SCN5A-Brugada syndrome automated patch clamp assay was generated and independently studied at Vanderbilt University Medical Center and Victor Chang Cardiac Research Institute. The assay was calibrated according to ClinGen Sequence Variant Interpretation recommendations using high-confidence variant controls (n=49). Normal and abnormal ranges of function were established based on the distribution of benign variant assay results. Odds of pathogenicity values were derived from the experimental results according to ClinGen Sequence Variant Interpretation recommendations. The calibrated assay was then used to study SCN5A variants of uncertain significance observed in 4 families with Brugada syndrome and other arrhythmia phenotypes associated with SCN5A loss-of-function.
UNASSIGNED: Variant channel parameters generated independently at the 2 research sites showed strong correlations, including peak INa density (R2=0.86). The assay accurately distinguished benign controls (24/25 concordant variants) from pathogenic controls (23/24 concordant variants). Odds of pathogenicity values yielded 0.042 for normal function and 24.0 for abnormal function, corresponding to strong evidence for both American College of Medical Genetics and Genomics/Association for Molecular Pathology benign and pathogenic functional criteria (BS3 and PS3, respectively). Application of the assay to 4 clinical SCN5A variants of uncertain significance revealed loss-of-function for 3/4 variants, enabling reclassification to likely pathogenic.
UNASSIGNED: This validated high-throughput assay provides clinical-grade functional evidence to aid the classification of current and future SCN5A-Brugada syndrome variants of uncertain significance.
UNASSIGNED: An in vitro SCN5A-Brugada syndrome automated patch clamp assay was generated and independently studied at Vanderbilt University Medical Center and Victor Chang Cardiac Research Institute. The assay was calibrated according to ClinGen Sequence Variant Interpretation recommendations using high-confidence variant controls (n=49). Normal and abnormal ranges of function were established based on the distribution of benign variant assay results. Odds of pathogenicity values were derived from the experimental results according to ClinGen Sequence Variant Interpretation recommendations. The calibrated assay was then used to study SCN5A variants of uncertain significance observed in 4 families with Brugada syndrome and other arrhythmia phenotypes associated with SCN5A loss-of-function.
UNASSIGNED: Variant channel parameters generated independently at the 2 research sites showed strong correlations, including peak INa density (R2=0.86). The assay accurately distinguished benign controls (24/25 concordant variants) from pathogenic controls (23/24 concordant variants). Odds of pathogenicity values yielded 0.042 for normal function and 24.0 for abnormal function, corresponding to strong evidence for both American College of Medical Genetics and Genomics/Association for Molecular Pathology benign and pathogenic functional criteria (BS3 and PS3, respectively). Application of the assay to 4 clinical SCN5A variants of uncertain significance revealed loss-of-function for 3/4 variants, enabling reclassification to likely pathogenic.
UNASSIGNED: This validated high-throughput assay provides clinical-grade functional evidence to aid the classification of current and future SCN5A-Brugada syndrome variants of uncertain significance.
摘要：
■Brugada综合征是一种遗传性心律失常，SCN5A中的功能丧失变体。解释SCN5A错义变体的致病性具有挑战性，在ClinVar中，约79%的SCN5A错义变异目前被归类为不确定意义的变异。自动化膜片钳技术可以实现离子通道变异体的高通量功能研究，并可以为变异体重新分类提供证据。
■产生了体外SCN5A-Brugada综合征自动膜片钳测定，并在范德比尔特大学医学中心和VictorChang心脏研究所进行了独立研究。根据ClinGen序列变体解释建议使用高置信度变体对照(n=49)校准测定。根据良性变异分析结果的分布，建立功能的正常和异常范围。根据ClinGen序列变体解释建议，从实验结果得出致病性值的可能性。然后使用校准的测定来研究在患有Brugada综合征的4个家庭中观察到的具有不确定显著性的SCN5A变体和与SCN5A功能丧失相关的其他心律失常表型。
■在两个研究地点独立生成的变体通道参数显示出强相关性，包括峰值INa密度(R2=0.86)。该测定准确区分良性对照(24/25一致变体)与致病性对照(23/24一致变体)。正常功能的致病性值的几率为0.042，异常功能的几率为24.0，与美国医学遗传学和基因组学学院/分子病理学良性和致病功能标准（分别为BS3和PS3）的有力证据相对应。对4种意义不确定的临床SCN5A变体的测定应用揭示了3/4变体的功能丧失，能够重新分类到可能的致病性。
■这种经过验证的高通量检测方法提供了临床级功能证据，有助于对当前和未来意义不确定的SCN5A-Brugada综合征变异进行分类。
■产生了体外SCN5A-Brugada综合征自动膜片钳测定，并在范德比尔特大学医学中心和VictorChang心脏研究所进行了独立研究。根据ClinGen序列变体解释建议使用高置信度变体对照(n=49)校准测定。根据良性变异分析结果的分布，建立功能的正常和异常范围。根据ClinGen序列变体解释建议，从实验结果得出致病性值的可能性。然后使用校准的测定来研究在患有Brugada综合征的4个家庭中观察到的具有不确定显著性的SCN5A变体和与SCN5A功能丧失相关的其他心律失常表型。
■在两个研究地点独立生成的变体通道参数显示出强相关性，包括峰值INa密度(R2=0.86)。该测定准确区分良性对照(24/25一致变体)与致病性对照(23/24一致变体)。正常功能的致病性值的几率为0.042，异常功能的几率为24.0，与美国医学遗传学和基因组学学院/分子病理学良性和致病功能标准（分别为BS3和PS3）的有力证据相对应。对4种意义不确定的临床SCN5A变体的测定应用揭示了3/4变体的功能丧失，能够重新分类到可能的致病性。
■这种经过验证的高通量检测方法提供了临床级功能证据，有助于对当前和未来意义不确定的SCN5A-Brugada综合征变异进行分类。
