Department of Fetal Medicine and Prenatal Diagnosis, The Third Affiliated Hospital of Guangzhou Medical University, Guangzhou, China.
Obstetrics and Gynecology Institute of Guangzhou, Guangzhou, China.
Prenat Diagn. 2020 Jul;40(8):918-924. doi: 10.1002/pd.5641. Epub 2020 Jun 4.
We aimed to investigate the validity of noninvasive prenatal diagnosis (NIPD) based on direct haplotype phasing without the proband or other family members and its feasibility for clinical application in the case of Duchenne muscular dystrophy (DMD).
Thirteen singleton-pregnancy families affected by DMD were recruited. The pathogenic variants in the pregnant females have been identified by multiplex ligation-dependent probe amplification (MLPA). We resolved maternal haplotypes for each family by performing targeted linked-read sequencing of their high molecular weight DNA, respectively. Then, we integrated the maternal haplotypes and the targeted sequencing results of maternal plasma DNA to infer the fetal haplotype and the DMD gene variant status. The fetal genotypes were further validated by using chorionic villus sampling.
The method of directly resolving maternal haplotype through targeted linked-read sequencing was smoothly performed in 12 participated families, but one failed (F11). The predicted variant status of 12 fetuses was correct, which had been confirmed by invasive prenatal diagnosis.
Direct haplotyping of NIPD based on linked-read sequencing for DMD is accurate.
我们旨在研究无先证者或其他家庭成员的直接单体型定相的无创性产前诊断（NIPD）的有效性及其在杜氏肌营养不良症（DMD）病例中的临床应用的可行性。
招募了 13 个受 DMD 影响的单胎妊娠家庭。通过多重连接依赖性探针扩增（MLPA）对孕妇中的致病变异进行了鉴定。我们分别对每个家庭的高分子量 DNA 进行靶向连接读取测序，以解析母体单倍型。然后，我们整合了母体单倍型和母体血浆 DNA 的靶向测序结果，以推断胎儿单倍型和 DMD 基因变异状态。通过绒毛膜绒毛取样进一步验证了胎儿基因型。
通过靶向连接读取测序直接解析母体单倍型的方法在 12 个参与的家庭中顺利进行，但一个家庭（F11）失败。12 个胎儿的预测变异状态是正确的，通过侵入性产前诊断得到了证实。
基于连接读取测序的 DMD 的 NIPD 直接单体型分析是准确的。
