BACKGROUND: Digital Polymerase Chain Reaction (dPCR) presents a promising approach for quantifying DNA and analyzing copy number variants, particularly in non-invasive prenatal testing. This method offers a streamlined and time-efficient procedure in contrast to the widely used next-generation sequencing for non-invasive prenatal testing. Studies have reported encouraging results for dPCR in detecting fetal autosomal aneuploidies. Consequently, this systematic review aimed to evaluate the effectiveness of dPCR in screening for trisomy 21, 18, and 13.
METHODS: A systematic search was conducted in PubMed, Web of Sciences, and Embase for relevant articles published up to December 30, 2023. The Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) was utilized for the quality assessment of the included articles. Furthermore, a bivariate random-effect regression model was used to conduct a meta-analysis on the utility of dPCR for trisomy 21 screening.
RESULTS: A total of 9 articles were included in this review, with all of them assessing the utility of dPCR in trisomy 21 screening, and 2 and 1 studies conducting additional analysis on the screening abilities of dPCR for trisomy 18 and 13, respectively. A bivariate random-effects model calculated pooled sensitivity and specificity with a 95% confidence interval (CI). Meta-analysis of 6 studies comparing trisomy-21 screening with karyotyping demonstrated dPCR\'s pooled sensitivity of 98% [95% CI: 94 -100] and specificity of 99% [95% CI: 99 -100]. While conducting a meta-analysis for trisomy 13 and 18 proved impractical, reported values for sensitivity and specificity were favorable.
CONCLUSIONS: These findings suggest that dPCR holds promise as an effective tool for non-invasive prenatal testing, presenting a less time-consuming and intricate alternative to next-generation sequencing. However, further research is necessary to evaluate dPCR\'s applicability in clinical settings and to delineate its specific advantages over next-generation sequencing. This study contributes valuable insights into the potential of dPCR for enhancing prenatal screening methodologies.
BACKGROUND: The protocol of this study was registered in the International Prospective Register of Systematic Reviews (PROSPERO) on 7/3/2024, with a registration code of CRD42024517523.

Tetralogy of Fallot (TOF) and double-outlet right ventricle (DORV) are conotruncal defects resulting from disturbances of the second heart field and the neural crest, which can occur as isolated malformations or as part of multiorgan syndromes. Their etiology is multifactorial and characterized by overlapping genetic causes. In this chapter, we present the different genetic alterations underlying the two diseases, which range from chromosomal abnormalities like aneuploidies and structural mutations to rare single nucleotide variations affecting distinct genes. For example, mutations in the cardiac transcription factors NKX2-5, GATA4, and HAND2 have been identified in isolated TOF cases, while mutations of TBX5 and 22q11 deletion, leading to haploinsufficiency of TBX1, cause Holt-Oram and DiGeorge syndrome, respectively. Moreover, genes involved in signaling pathways, laterality determination, and epigenetic mechanisms have also been found mutated in TOF and/or DORV patients. Finally, genome-wide association studies identified common single nucleotide polymorphisms associated with the risk for TOF.

Ventricular septal defects (VSDs) are recognized as one of the commonest congenital heart diseases (CHD), accounting for up to 40% of all cardiac malformations, and occur as isolated CHDs as well as together with other cardiac and extracardiac congenital malformations in individual patients and families. The genetic etiology of VSD is complex and extraordinarily heterogeneous. Chromosomal abnormalities such as aneuploidy and structural variations as well as rare point mutations in various genes have been reported to be associated with this cardiac defect. This includes both well-defined syndromes with known genetic cause (e.g., DiGeorge syndrome and Holt-Oram syndrome) and so far undefined syndromic forms characterized by unspecific symptoms. Mutations in genes encoding cardiac transcription factors (e.g., NKX2-5 and GATA4) and signaling molecules (e.g., CFC1) have been most frequently found in VSD cases. Moreover, new high-resolution methods such as comparative genomic hybridization enabled the discovery of a high number of different copy number variations, leading to gain or loss of chromosomal regions often containing multiple genes, in patients with VSD. In this chapter, we will describe the broad genetic heterogeneity observed in VSD patients considering recent advances in this field.

DNA alterations in gametes, which may occur either spontaneously or as a result of exposure to genotoxicants, can lead to constitutional chromosomal anomalies in the offspring. Alcohol is an established genotoxicant. The goal of this hypothesis-testing longitudinal cohort study was to evaluate the effect of significant/sustained maternal alcohol exposure on clinically diagnosed constitutional chromosomal anomalies among children diagnosed with fetal alcohol syndrome (FAS). De-identified eligibility and claim healthcare records, prospectively generated from the 1990-2012 Florida Medicaid system within the Independent Healthcare Research Database (IHRD), were analyzed. Children examined were continuously eligible with ≥ 8 outpatient office visits during the 96-month period following birth. Among these children, 377 were diagnosed with FAS and 137,135 were not. The incidence rate of chromosomal anomalies involving segregation (trisomy 13, 18, or 21, n = 625), microdeletions (microdeletion syndromes, n = 39), and point mutations (sickle-cell anemia/cystic fibrosis, n = 2570) were examined using frequency risk ratio (RR) and logistic regression (adjusted odds ratio (aOR) for sex, race, residence, socioeconomic/environmental exposure status, and birth date) models. The incidence rates of chromosomal anomalies involving segregation (RR=5.92, aOR=5.85) and microdeletions (RR=41.6, aOR=34.1) were significantly increased in the FAS cohort as compared to the non-diagnosed cohort, but there was no difference in the incidence rate of point mutations (RR=1.14, aOR=1.29). Maternal toxicant exposure should be considered in the etiology of constitutional chromosomal anomaly in offspring.

Trisomy is the presence of one extra copy of an entire chromosome or its part in a cell nucleus. In humans, autosomal trisomies are associated with severe developmental abnormalities leading to embryonic lethality, miscarriage or pronounced deviations of various organs and systems at birth. Trisomies are characterized by alterations in gene expression level, not exclusively on the trisomic chromosome, but throughout the genome. Here, we applied the high-throughput chromosome conformation capture technique (Hi-C) to study chromatin 3D structure in human chorion cells carrying either additional chromosome 13 (Patau syndrome) or chromosome 16 and in cultured fibroblasts with extra chromosome 18 (Edwards syndrome). The presence of extra chromosomes results in systematic changes of contact frequencies between small and large chromosomes. Analyzing the behavior of individual chromosomes, we found that a limited number of chromosomes change their contact patterns stochastically in trisomic cells and that it could be associated with lamina-associated domains (LAD) and gene content. For trisomy 13 and 18, but not for trisomy 16, the proportion of compacted loci on a chromosome is correlated with LAD content. We also found that regions of the genome that become more compact in trisomic cells are enriched in housekeeping genes, indicating a possible decrease in chromatin accessibility and transcription level of these genes. These results provide a framework for understanding the mechanisms of pan-genome transcription dysregulation in trisomies in the context of chromatin spatial organization.

We report a case of double aneuploidy in a preterm male newborn with karyotype 48,XXY,+18 whose mother was of advanced age and infected with the SARS-CoV-2 virus during the early stages of her pregnancy. The clinical features observed in the newborn included intrauterine growth retardation, dysmorphic facial features, overlapping fingers on both hands, respiratory distress syndrome, ventricular septal defect, patent ductus arteriosus, persistent pulmonary hypertension, and bilateral clubfoot, a phenotype that mainly correlates with Edwards syndrome (trisomy 18). To our knowledge, this is the first reported case of double aneuploidy in Croatia. This paper provides a detailed description of the clinical presentation and treatment strategies used, with the aim of providing valuable data for future recognition and management of similar cases. Furthermore, we discuss the mechanisms of nondisjunction that might account for this rare form of aneuploidy.

The survival rate of patients with trisomy 13 and trisomy 18 has increased dramatically over the past two decades. We sought to comprehensively describe the otolaryngologic clinical characteristics and procedures required for these patients at our institution.
We performed algorithmic identification of patients with a diagnosis of trisomy 13 and trisomy 18 for whom the otolaryngology service provided inpatient or outpatient care at our institution between the dates of February 1997 and March 2021.
Of the 47 patients studied, 18 patients had a diagnosis of trisomy 13, and 29 had a diagnosis of trisomy 18. Complete trisomy was present in 44% (8/18) of trisomy 13 patients and 55% (16/29) of trisomy 18 patients. 81% of patients were living at the time of the study. About 94% (44/47) of patients required consultation with another specialty in addition to Otolaryngology. Overall, the most common diagnoses among this cohort were gastroesophageal reflux disease (47%), dysphagia (40%), otitis media (38%), and obstructive sleep apnea (34%). Nearly three-quarters (74%) of patients studied required an otolaryngologic procedure. The most common surgical procedure was tonsillectomy and/or adenoidectomy. Patients with trisomy 18 were significantly more likely to have external auditory canal stenosis and obstructive sleep apnea whereas patients with trisomy 13 were more likely to have cleft lip and palate.
Patients with a diagnosis of trisomy 13 or 18 often require multidisciplinary management and the range of required care spans the breadth of otolaryngology.
4 Laryngoscope, 133:1501-1506, 2023.

Trisomy 18 is an autosomal chromosomal disorder, which is associated with numerous ranges of congenital anomalies. Purpose of this largest study in Poland was to analyze diagnosis and follow-up of fetuses with the prenatal diagnosis of Trisomy 18 in our tertiary center.
The study was conducted in a tertiary center for fetal cardiology. The inclusion criteria comprised fetuses with karyotype of Trisomy 18. Data on number of delivery, number of pregnancy, cardiac and extracardiac diseases, type and date of childbirth, sex, birth date, Apgar score, survival time and autopsy were analyzed.
There were 41 fetuses with diagnosis confirmed by amniocentesis: 34 were females, 7 males. CHD was detected prenatally in 73% cases at mean gestational age of 26 weeks. The most common CHD was AV-canal (13 cases, 43%) and VSD (13 cases, 43%). In 1999-2010 the average time to detect a heart defect was 29 weeks, in 2011-2021 it was 23 weeks (p < 0.01, U-Mann-Whitney). IUGR was diagnosed in the 3rd trimester in 29 cases (70%), polyhydramnion in 21 cases (51%).
Congenital heart defects in female fetuses with intrauterine growth restriction in 3rd trimester with polyhydramnios and in subsequent pregnancy, regardless of maternal age, were typical prenatal findings for Trisomy 18. Heart defects with incomplete septum such as AVC or VSD (which nowadays can be detected in the 1st half of the pregnancy) were the most common anomaly in Edwards Syndrome. These heart defects did not require intervention in the early neonatal period.

OBJECTIVE: The main objective of this study was to evaluate parents\' current demands following the announcement of trisomy 18 and maternal risks.
METHODS: A single-centre retrospective study was performed in the Paris Saclay Foetal Medicine Department from 2018 to 2021. All patients followed up in the department who had cytogenetic confirmation of trisomy 18 were included.
RESULTS: 89 patients were recruited. The most common malformations at ultrasound examination were cardiac or brain abnormalities, distal arthrogryposis as well as severe intrauterine growth retardation. 29% of foetuses with trisomy 18 had more than three malformations. 77.5% of patients requested medical termination of pregnancy. Among the 19 patients who chose to continue their pregnancy, 10 (52.6%) presented with obstetrical complications, of which 7 (41.2%) experienced stillbirth; five babies were born alive with no survival at 6 months.
CONCLUSIONS: In France, in the case of foetal trisomy 18, most women request termination of pregnancy. In the post-natal period, the management of a newborn with trisomy 18 is oriented towards palliative care. The mother\'s risk of obstetrical complications should be part of counselling. Follow-up, support and safety should be the goal of management of these patients, regardless of the patient\'s choice.

OBJECTIVE: To perform a statewide characteristics and outcomes analysis of the Trisomy 18 (T18) population and explore the potential impact of associated congenital heart disease (CHD) and congenital heart surgery.
METHODS: Retrospective review of the Texas Hospital Inpatient Discharge Public Use Data File between 2009 and 2019, analysing discharges of patients with T18 identified using ICD-9/10 codes. Discharges were linked to analyse patients. Demographic characteristics and available outcomes were evaluated. The population was divided into groups for comparison: patients with no documentation of CHD (T18NoCHD), patients with CHD without congenital heart surgery (T18CHD), and patients who underwent congenital heart surgery (T18CHS).
RESULTS: One thousand one hundred fifty-six eligible patients were identified: 443 (38%) T18NoCHD, 669 (58%) T18CHD, and 44 (4%) T18CHS. T18CHS had a lower proportion of Hispanic patients (n = 9 (20.45%)) compared to T18CHD (n = 315 (47.09%)), and T18NoCHD (n = 219 (49.44%)) (p < 0.001 for both). Patients with Medicare/Medicaid insurance had a 0.42 odds ratio (95%CI: 0.20-0.86, p = 0.020) of undergoing congenital heart surgery compared to private insurance. T18CHS had a higher median total days in-hospital (47.5 [IQR: 12.25-113.25] vs. 9 [IQR: 3-24] and 2 [IQR: 1-5], p < 0.001); and a higher median number of admissions (n = 2 [IQR: 1-4]) vs. 1 [IQR: 1-2] and 1 [IQR: 1-1], (p < 0.001 for both). However, the post-operative median number of admissions for T18CHS was 0 [IQR: 0-2]. After the first month of life, T18CHS had freedom from in-hospital mortality similar to T18NoCHD and superior to T18CHD.
CONCLUSIONS: Short-term outcomes for T18CHS patients are encouraging, suggesting a freedom from in-hospital mortality that resembles the T18NoCHD. The highlighted socio-economic differences between the groups warrant further investigation. Development of a prospective registry for T18 patients should be a priority for better understanding of longer-term outcomes.