Background: Increased nuchal translucency (NT) is an important biomarker associated with increased risk of fetal structural anomalies. It is known to be contributed by a wide range of genetic etiologies from single-nucleotide variants to those affecting millions of base pairs. Currently, prenatal diagnosis is routinely performed by karyotyping and chromosomal microarray analysis (CMA); however, both of them have limited resolution. The diversity of the genetic etiologies warrants an integrated assay such as genome sequencing (GS) for comprehensive detection of genomic variants. Herein, we aim to evaluate the feasibility of applying GS in prenatal diagnosis for the fetuses with increased NT. Methods: We retrospectively applied GS (> 30-fold) for fetuses with increased NT (≥3.5 mm) who underwent routine prenatal diagnosis. Detection of single-nucleotide variants, copy number variants, and structural rearrangements was performed simultaneously, and the results were integrated for interpretation in accordance with the guidelines of the American College of Medical Genetics and Genomics. Pathogenic or likely pathogenic (P/LP) variants were selected for validation and parental confirmation, when available. Results: Overall, 50 fetuses were enrolled, including 34 cases with isolated increased NT and 16 cases with other fetal structural malformations. Routine CMA and karyotyping reported eight P/LP CNVs, yielding a diagnostic rate of 16.0% (8/50). In comparison, GS provided a twofold increase in diagnostic yield (32.0%, 16/50), including one mosaic turner syndrome, eight cases with microdeletions/microduplications, and seven cases with P/LP point mutations. Moreover, GS identified two cryptic insertions and two inversions. Follow-up study further demonstrated the potential pathogenicity of an apparently balanced insertion that disrupted an OMIM autosomal dominant disease-causing gene at the insertion site. Conclusions: Our study demonstrates that applying GS in fetuses with increased NT can comprehensively detect and delineate the various genomic variants that are causative to the diseases. Importantly, prenatal diagnosis by GS doubled the diagnostic yield compared with routine protocols. Given a comparable turnaround time and less DNA required, our study provides strong evidence to facilitate GS in prenatal diagnosis, particularly in fetuses with increased NT.

This study aims to investigate the value of chromosomal microarray analysis (CMA) and whole exome sequencing (WES) in fetuses with increased nuchal translucency (defined as NT above the 95th centile for the crown-rump length). A total of 374 singleton pregnancies with gestational ages ranging from 11 to 13 + 6 weeks were investigated. Ultrasound displayed increased NT and no detectable structural malformations in these fetuses. Pregnancies were divided into 4 groups according to the NT values: 95th centile-3.4 mm (114 cases); 3.5-4.4 mm (150 cases); 4.5-5.4 mm (55 cases); and ≥5.5 mm (55 cases). The possible chromosomal anomalies were all analyzed by CMA first. Furthermore, 24 cases with increased NT but negative CMA results were investigated by WES, and the outcomes were followed up. Among all the 374 cases, causative genetic defects were detected in 100/374 (26.7%) of the cases along with 9 variants of unknown significance (VOUS) by CMA. CMA testing yielded 30 pathogenic variants (30/55), accounting for a detection rate of 54.5%, and 1 VOUS in the group of NT ≥5.5 mm, indicating the highest detection rate in the 4 groups. The 24 cases of the CMA negative sub-cohort with WES analysis further yielded 2 VOUS and 3 likely pathogenic variants, including 2 dominant de novo mutations in SOS1 and ECE1 and 1 recessive inherited compound heterozygous mutation in PIGN, which are associated with cardiac defects. All 3 cases opted for termination of pregnancy (TOP). In addition, 2 cases with increased NT were negative by both CMA and WES analysis, and fetal demise occurred. In conclusion, for the investigation of fetuses with increased NT exome sequencing is suggested to be considered in cases with negative CMA findings. However, appropriate genetic counseling should be given to optimizing its utilization in prenatal diagnosis.

IL-17A and IL-17F, which are produced by Th17 cells, were elevated (IL-17A: clopidogrel, 237AE8 pg mL )1 ; control, not detected; and IL-17F: clopidogrel, 187AE3 pg mL )1 ; control, not detected). On the other hand, the serum IL-17A level was below the detection limit (< 60 pg mL )1 ), and the serum IL-17F level was elevated (clopidogrel, 265AE0 pg mL )1 ; control, 120AE2 pg mL )1 ).AGEP is a rare and severe skin eruption, of which 90% of cases are induced by drugs such as antibiotics, calcium channel blockers, carbamazepine, antimycotics, nonsteroidal antiinflammatory drugs and paracetamol, 3 but clopidogrel has not previously been reported as a cause of AGEP.The mechanism of AGEP is not fully understood, but drugspecific CD4+ T cells have been considered to be involved in neutrophil-rich inflammatory responses and to orchestrate the immune reaction directly by the production of IL-8, a chemoattractant for neutrophils. 4 On the other hand, it has also been hypothesized that AGEP might be induced indirectly via the production of IL-17, which that induces IL-8 production; 5 however, this has not yet been proven. In this report, we have presented the first case of AGEP with a positive DLST for clopidogrel, and elevated IL-17A and IL-17F in the culture supernatant. Although it is limited to a single case, our study suggests that Th17 may be involved in the pathogenesis of AGEP.

Objective To evaluate the utility of expanded non‐invasive prenatal screening (NIPS), compared with chromosomal microarray analysis (CMA), for the detection of chromosomal abnormalities in high‐risk pregnancies. Methods This was a multicenter retrospective study of singleton pregnancies at high risk for chromosomal abnormality. Patients who underwent expanded NIPS and CMA sequentially during pregnancy from 2015 to 2019 were included in the analysis. Pregnancies with a positive result for sex chromosome aneuploidy were excluded as the full details could not be retrieved. The utility of expanded NIPS and CMA for detection of chromosomal abnormalities in this cohort was compared by assessing the concordance between the results. Results Of the 774 included high‐risk pregnancies, 550 (71.1%) had a positive NIPS result, while a positive CMA result was detected in 308 (39.8%) cases. The rate of full or partial concordance between NIPS and CMA was 82.2%, 59.6% and 25.0% for trisomies 21, 18 and 13, respectively. For rare aneuploidies and segmental imbalances, NIPS and CMA results were fully or partially concordant in 7.5% and 33.3% of cases, respectively. Copy‐number variants < 5 Mb were detected more often by CMA, with an incidence of 7.9% (61/774) compared with 3.1% (24/774) by NIPS. A genetic aberration was detected by CMA in 1 in 17 (5.8%) high‐risk pregnancies that had a negative or non‐reportable NIPS result. Conclusion CMA allows for comprehensive detection of genome‐wide chromosomal abnormalities in high‐risk pregnancies. CMA should be offered instead of expanded NIPS for high‐risk pregnancies. Copyright © 2020 ISUOG. Published by John Wiley & Sons Ltd.

Objective To analyze the fetal fraction, fetal sex, and chromosomal aneuploidy in multiple pregnancies using noninvasive prenatal testing (NIPT). Method A total of 362 pregnant women including 203 singleton pregnancies, 69 twins, and 90 higher‐order multiple pregnancies were recruited. Fetal fractions estimated by size ratio‐based and Y chromosome‐based approaches in singleton pregnancies with male fetus were used as source data to establish the model. The model was then applied to multiple pregnancies for fetal fraction estimation. By comparing the fetal fractions estimated by size ratio to those estimated by Y chromosome or autosomal chromosomes, fetal sex and chromosomal aneuploidy can be analyzed. Results The size ratio‐based approach has been well established in estimating fetal fractions for twin and higher‐order multiple pregnancies. Fetal fraction had a positive correlation with gestational age in twin and triplet pregnancies. Fetal sex was determined with accuracies of 98.6% (95% CI, 92.19%‐99.96%) in twins and 97.6% (95% CI, 91.76%‐99.71%) in triplet pregnancies. Four trisomy 21, one trisomy 18, and one trisomy 13 cases were detected by NIPT. Two trisomy 21 singleton pregnancies and one trisomy 21 twin pregnancy were confirmed by karyotyping. Conclusion Fetal sex and chromosomal aneuploidy in multiple pregnancies can be determined using NIPT.

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Objectives: To evaluate the performance of noninvasive prenatal sequencing for multiple Mendelian monogenic disorders (NIPS-M) among fetuses with skeletal abnormalities or increased nuchal translucency (NT). Methods: Pregnancies with fetal skeletal abnormalities or increased NT (≥3.0 mm) observed by ultrasonography were recruited between October 2017 and March 2019. Parental blood from 13 couples were collected for NIPS-M testing reported. All the NIPS-M results were followed up by invasive diagnostic testing or neonatal examination. Results: Among the 13 cases, 8 (61.5%) yielded positive results for pathogenic variants in the FGFR3, COL1A1, RAF1, PTPN11 and SOS1 genes by NIPS-M. One case was excluded for further analysis due to insufficient fetal DNA (<4.5%). De novo mutations were reported in six of the eight positive cases (75%). The other two were inconclusive as the pathogenic variants were detected in both plasma and genomic DNA of the mothers. The sensitivity of NIPS-M was 100%. Conclusions: Our pilot study demonstrates that NIPS-M is an accurate approach for detection of multiple monogenic disorders among fetuses with skeletal abnormalities or increased NT. It serves as an alternative and highly sensitive method to provide valuable molecular information for these groups of women who are reluctant to undergo invasive procedure.

Background To assess the indications and complications of late amniocentesis and the advanced genetic test results in a tertiary university fetal medical medicine unit. Methods In this retrospective study, women that underwent amniocentesis at 24+ 0 to 39+ 4 weeks, between January 2014 and December 2019, were recruited. Indications, complications, genetic test results, and pregnancy outcomes were reported for each pregnancy and compared with those who underwent the traditional amniocentesis at 16+ 0 to 23+ 6 weeks (control group). Information was retrieved from patient medical records, checked by research staff, and analyzed. Results Of the 1287 women (1321 fetuses) included in the late amniocentesis group, late detected sonographic abnormalities (85.5%) were the most common indication. The overall incidence of preterm birth and intrauterine demise after amniocentesis were 2.5 and 1.3%, respectively. Sixty-nine fetuses with aneuploidy (5.3%) and seventy-two fetuses with pathogenic copy number variations (5.5%) were identified by chromosomal microarray analysis. The maximal diagnostic yield (70%) was in the subgroup of fetuses with the abnormal diagnostic test results, followed by abnormal NIPT results (35.7%) and multiple abnormalities (23.8%). And 35.4% of the pregnancies were finally terminated. Conclusions Due to the high detection rates of advanced genetic technologies and the safety of the invasive procedure (3.9% vs 4.0%), it is reasonable to recommend late amniocentesis as an effective and reliable method to detect late-onset fetal abnormalities. However, chromosomal microarray and whole-exome sequencing may result in uncertain results like variants of uncertain significance. Comprehensive genetic counseling is necessary.