Department of Laboratory Medicine, Azienda Ospedaliera Universitaria Città della Salute e della Scienza, Turin, Italy.
Department of Obstetrics and Gynecology (St Anna Hospital), Azienda Ospedaliera Universitaria Città della Salute e della Scienza, Turin, Italy.
Prenat Diagn. 2021 Dec;41(13):1694-1700. doi: 10.1002/pd.6050. Epub 2021 Oct 7.
To assess the efficacy of cell-free (cf)DNA screening for aneuploidy using the automated system based on rolling circle replication.
A prospective study among women referred for invasive prenatal diagnosis between July 2018 and December 2019. The plasma fraction was extracted within 5 days from blood collection, stored at -20°C and cfDNA measured between January and December 2019.
A total of 805 women were recruited; 778 with singleton pregnancies and 27 twins. There were 48 Down syndrome, 25 Edwards syndrome and 3 Patau syndrome cases. Overall, the no-call rate was 2.6% (95% confidence interval 1.6%-3.9%) which reduced from 4.7% to 1.1% after relocation of the system (p < 0.002) to ensure a constant ambient temperature below 25°C. In singletons the Down syndrome detection rate (DR) was 100% (93%-100%) and false-positive rate (FPR) 0.14% (0.00%-0.79%). The Edwards syndrome DR was 96% (80%-100%) and FPR 0.78% (0.29%-1.7%). One false-positive had a confined placental trisomy 18 and the remaining five a z-score requiring sample repetition; all the false-positives occurred before system relocation (p < 0.005). Patau syndrome DR and FPR were 67% (9.4%-99%) and 0.26% (0.03%-0.95%).
The cfDNA rolling circle method yields similar results to other methods provided that room temperature is adequately controlled.
评估基于滚环复制的自动化系统进行无细胞（cf）DNA 非整倍体筛查的效果。
这是一项 2018 年 7 月至 2019 年 12 月期间进行的针对有侵入性产前诊断指征的女性的前瞻性研究。采血后 5 天内提取血浆部分，-20°C 储存，并于 2019 年 1 月至 12 月间测量 cfDNA。
共招募 805 名女性；其中 778 名怀有单胎妊娠，27 名怀有双胞胎。48 例唐氏综合征，25 例爱德华氏综合征，3 例帕陶氏综合征。总的来说，无信号率为 2.6%（95%置信区间 1.6%-3.9%），在系统搬迁后（p<0.002），无信号率从 4.7%降低至 1.1%，以确保环境温度稳定在 25°C 以下。在单胎妊娠中，唐氏综合征的检出率（DR）为 100%（93%-100%），假阳性率（FPR）为 0.14%（0.00%-0.79%）。爱德华氏综合征的 DR 为 96%（80%-100%），FPR 为 0.78%（0.29%-1.7%）。1 例假阳性为局限性胎盘 18 三体，其余 5 例为需重复样本的 Z 评分；所有假阳性均发生在系统搬迁前（p<0.005）。帕陶氏综合征的 DR 和 FPR 分别为 67%（9.4%-99%）和 0.26%（0.03%-0.95%）。
cfDNA 滚环法的结果与其他方法相似，前提是室温得到充分控制。
