Obsterics and Gynecology Unit, Nigist Eleni Mohammad Memorial Referral Hospital, Hossana, Ethiopia.
Department of Biotechnology, College of Natural and Computational Science, Wachemo University, Hosaena, Ethiopia.
PLoS One. 2022 Mar 17;17(3):e0265583. doi: 10.1371/journal.pone.0265583. eCollection 2022.
A majority of non-invasive prenatal screening studies determining fetal RhD status have been tested on Caucasian and Asian populations, but limited or no studies have been conducted on the Ethiopian population. In the current study, we carried non-invasive prenatal screening of fetal RHD genotype in selected RhD negative Ethiopian pregnant women.
Cell-free DNA was extracted from the plasma samples of 117 RhD pregnant women between 9 and 38 weeks of gestation. Fetal RHD genotypes were detected by targeting exons 5, 7 and 10 of the RHD gene by using real-time PCR assay. RHD genotypic results were confirmed by neonatal cord blood serology.
Fetal RHD genotyping was conclusive in all 117 subjects. RHD genotype was correctly predicted in 115 of 117 cases, thus the test yielded 98.3% accuracy (95%CI: 97.3-99.1%). Among 115 cases, 105 were genotyped as RHD positive and 12 were genotyped as RHD negative. The sensitivity and specificity of the test were 99.1% (95% CI: 94.8-99.9%) and 91.7% (95%CI: 61.5-99.7%) respectively. The negative and positive predictive values were 99.9% (95%CI: 99.2-99.9%) and 54.0% (95% CI: 15.2-88.4%) respectively. SRY genotyping results were in complete concordance with fetal sex.
Multi exon targeted non-invasive prenatal screening test for fetal RhD determination exhibited high accuracy and sensitivity. A confirmatory study with a bigger size of study subjects is warranted before enabling clinical implementation.
大多数确定胎儿 RhD 状态的非侵入性产前筛查研究都是在白人和亚洲人群中进行的，但在埃塞俄比亚人群中进行的研究有限或没有。在目前的研究中，我们对选定的 RhD 阴性埃塞俄比亚孕妇进行了胎儿 RHD 基因型的非侵入性产前筛查。
从 117 名妊娠 9 至 38 周的 RhD 孕妇的血浆样本中提取无细胞 DNA。通过使用实时 PCR 检测针对 RHD 基因的外显子 5、7 和 10 来检测胎儿 RHD 基因型。通过新生儿脐带血血清学检测确认 RHD 基因型结果。
所有 117 例均完成了胎儿 RHD 基因分型。117 例中有 115 例正确预测了 RHD 基因型，因此该检测的准确率为 98.3%（95%CI：97.3-99.1%）。在 115 例中，105 例为 RHD 阳性基因型，12 例为 RHD 阴性基因型。该检测的灵敏度和特异性分别为 99.1%（95%CI：94.8-99.9%）和 91.7%（95%CI：61.5-99.7%）。阴性和阳性预测值分别为 99.9%（95%CI：99.2-99.9%）和 54.0%（95%CI：15.2-88.4%）。SRY 基因分型结果与胎儿性别完全一致。
针对胎儿 RhD 确定的多外显子靶向非侵入性产前筛查检测具有高准确性和灵敏度。在允许临床实施之前，需要进行更大规模的研究对象验证研究。
