Supplementary Material for: The Diagnostic Yield of Prenatal Genetic Technologies in Congenital Heart Disease: A Prospective Cohort Study

Introduction: The objective was to evaluate: (i) the proportion of prenatally diagnosed congenital heart disease (CHD) associated with an abnormal quantitative fluorescence-PCR (QF-PCR), chromosome microarray (CMA), and exome sequencing (ES) result; and (ii) the diagnostic yield of these technologies based on CHD category and presence of extra-cardiac anomalies (ECAs). Methods: This prospective cohort study was set across 12 UK foetal medicine centres. All cases underwent QF-PCR, CMA, and ES, and the diagnostic yield in n = 147 cases of prenatally diagnosed CHD was assessed. Results: In 34.7% (n = 51/147), a genetic diagnosis was obtained. Using a stepwise testing strategy, the diagnostic yield for QF-PCR, CMA, and ES was 15.6% (n = 23/147), 13.7% (n = 17/124), and 10.2% (n = 11/107), respectively. Abnormal QF-PCR/shunt (septal) defects 31.4% (n = 11/35), p = 0.046, and abnormal CMA/conotruncal anomalies 22.7% (n = 10/44), p = 0.04, had significant associations. Monogenic variants were commonest in complex CHD 36.4% (n = 4/11). Multisystem CHD had a greater diagnostic yield overall compared to isolated OR 2.41 (95% CI, 1.1–5.1), particularly in association with brain and gastrointestinal tract anomalies. The proportion of variants of uncertain significance was 4.7% (n = 5/107) with ES, with none in the CMA group. Conclusion: In the era of prenatal ES, there remains an important role for QF-PCR and CMA. Identification of monogenic pathologic variants further allows delineation of prognosis in CHD.

研究目的为评估两项内容：(i) 产前诊断的先天性心脏病（congenital heart disease, CHD）中，合并异常定量荧光聚合酶链反应（quantitative fluorescence-PCR, QF-PCR）、染色体微阵列（chromosome microarray, CMA）及外显子测序（exome sequencing, ES）结果的病例占比；(ii) 基于先天性心脏病分类及心外畸形（extra-cardiac anomalies, ECAs）存在情况的各类检测技术诊断检出率。方法：本研究为一项前瞻性队列研究，在英国12家胎儿医学中心开展。所有入组病例均接受QF-PCR、CMA及ES检测，对147例产前诊断的先天性心脏病病例的诊断检出率进行评估。结果：本研究中共34.7%（n=51/147）的病例获得遗传学诊断。采用分步检测策略时，QF-PCR、CMA及ES的诊断检出率分别为15.6%（n=23/147）、13.7%（n=17/124）及10.2%（n=11/107）。异常QF-PCR结果与间隔（分流型）缺损的关联具有统计学显著性（31.4%，n=11/35，p=0.046），异常CMA结果与圆锥动脉干畸形的关联同样具有统计学显著性（22.7%，n=10/44，p=0.04）。单基因变异在复杂性先天性心脏病中最为常见，占比36.4%（n=4/11）。多系统先天性心脏病的整体诊断检出率高于孤立性先天性心脏病（比值比（odds ratio, OR）=2.41，95%置信区间（confidence interval, CI）：1.1~5.1），合并脑部及胃肠道畸形时该优势尤为显著。采用ES检测时，意义未明变异的占比为4.7%（n=5/107），CMA组未检出此类变异。结论：在产前外显子测序应用的当下，QF-PCR与CMA仍具有重要临床价值。检出单基因致病性变异可进一步明确先天性心脏病的预后情况。