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Noninvasive cfDNA testing for monogenic disorders (sgNIPT) has become integrated into the care of pregnant women at increased risk based on carrier status, known family history, or ultrasound anomalies. The availability of commercial tests for common autosomal recessive and de novo autosomal dominant conditions has led to the use of these tests in low‐risk pregnancies. However, is the technology ready for use in this low‐risk population? This report is a summary of the debate on this topic at the 27th International Conference on Prenatal Diagnosis and Therapy. Both expert debaters provided strong arguments in favor and against the use of sgNIPT in low‐risk pregnancies. The argument in favor of sgNIPT for autosomal recessive conditions is that it allows the identification of affected pregnancies without the need for involving the partner in testing. Arguments for sgNIPT for autosomal dominant conditions include identification of affected fetuses that would have either presented later in pregnancy with fetal anomalies or not been detected prenatally given normal ultrasounds, respect for patient autonomy and patient desire for information. Strong arguments were made against offering sgNIPT screening. Given that traditional carrier screening for recessive conditions can be carried out in many jurisdictions, the added value of sgNIPT has not been clearly demonstrated. Arguments against sgNIPT for autosomal dominant conditions included the total lack of clinical validation studies and the risk of false reassurance in cases of negative results and unnecessary invasive procedures in cases of false positive results. Although there is a desire to take advantage of new technologies to improve the detection of monogenic disorders in low‐risk populations, based on the discussion and the audience vote, it appears premature to offer sgNIPT to all low risk pregnant women. Further clinical validation studies are needed prior to broad implementation. Key points: What's already known about this topic?cfDNA testing on maternal blood is technically possible and commercially available for dominant and recessive monogenic conditions. What does the study add?This report summarizes an oral debate presented at the 27th International Conference on Prenatal Diagnosis and Therapy in Edinburgh, UK on June 20th, 2023.The benefits, limitations and challenges of performing cfDNA screening for monogenic conditions in low‐risk populations are discussed. [ABSTRACT FROM AUTHOR]

Genetic and genomic technologies can effectively diagnose numerous genetic disorders. Patients benefit when genetic counselling accompanies genetic testing and international guidelines recommend pre‐ and post‐test genetic counselling with genome‐wide sequencing. However, there is a gap in knowledge regarding the unique genetic counselling considerations with different types of genetic testing in the Neonatal Intensive Care Unit (NICU) and the Pediatric Intensive Care Unit (PICU). This scoping review was conducted to identify the gaps in care with respect to genetic counselling for infants/pediatric patients undergoing genetic and genomic testing in NICUs and PICUs and understand areas in need of improvement in order to optimize clinical care for patients, caregivers, and healthcare providers. Five databases (MEDLINE [Ovid], Embase [Ovid], PsycINFO [Ebsco], CENTRAL [Ovid], and CINHAL [Ebsco]) and grey literature were searched. A total of 170 studies were included and used for data extraction and analysis. This scoping review includes descriptive analysis, followed by a narrative account of the extracted data. Results were divided into three groups: pre‐test, post‐test, and comprehensive (both pre‐ and post‐test) genetic counselling considerations based on indication for testing. More studies were conducted in the NICU than the PICU. Comprehensive genetic counselling was discussed in only 31% of all the included studies demonstrating the need for both pre‐test and post‐test genetic counselling for different clinical indications in addition to the need to account for different cultural aspects based on ethnicity and geographic factors. [ABSTRACT FROM AUTHOR]

When genetic tests are not funded publicly, out‐of‐pocket (OOP) pay options may be discussed with patients. We evaluated trends in genetic testing and OOP pay for two publicly funded British Columbia clinical programs serving >12 000 patients/year (The Hereditary Cancer Program [HCP] and Provincial Medical Genetics Program [PMGP]) between 2015–2019. Linear and regression models were used to explore the association of OOP pay with patient demographic variables at HCP. An interrupted time series and linear and logistic regression models were used on PMGP data to examine the effect of a change in the funding body. The total number of tests completed through PMGP, and HCP increased by 260% and 320%, respectively. OOP pay increased at HCP by 730%. The mean annual income of patients who paid OOP at HCP was ≥$3500 higher than in the group with funded testing (p < 0.0001). The likelihood of OOP pay increased at PMGP before the funding body change (OR per month: 1.07; 95% CI: 1.04, 1.10); while this likelihood had an immediate 87% drop when the change occurred (OR: 0.13; 95% CI: 0.06, 0.32). Patients with higher incomes are more likely to pay OOP. Financial barriers can create disparities in clinical outcomes. Funding decisions have a significant impact on rate of OOP pay. [ABSTRACT FROM AUTHOR]

Background: Congenital anomalies (CA) are one of the leading causes of infant mortality and long‐term disability. Many jurisdictions rely on health administrative data to monitor these conditions. Case definition algorithms can be used to monitor CA; however, validation of these algorithms is needed to understand the strengths and limitations of the data. This study aimed to validate case definition algorithms used in a CA surveillance system in British Columbia (BC), Canada. Methods: A cohort of births between March 2000 and April 2002 in BC was linked to the Health Status Registry (HSR) and the BC Congenital Anomalies Surveillance System (BCCASS) to identify cases and non‐cases of specific anomalies within each surveillance system. Measures of algorithm performance were calculated for each CA using the HSR as the reference standard. Agreement between both databases was calculated using kappa coefficient. The modified Standards for Reporting Diagnostic Accuracy guidelines were used to enhance the quality of the study. Results: Measures of algorithm performance varied by condition. Positive predictive value (PPV) ranged between approximately 73%–100%. Sensitivity was lower than PPV for most conditions. Internal congenital anomalies or conditions not easily identifiable at birth had the lowest sensitivity. Specificity and negative predictive value exceeded 99% for all algorithms. Conclusion: Case definition algorithms may be used to monitor CA at the population level. Accuracy of algorithms is higher for conditions that are easily identified at birth. Jurisdictions with similar administrative data may benefit from using validated case definitions for CA surveillance as this facilitates cross‐jurisdictional comparison. [ABSTRACT FROM AUTHOR]

Purpose and scope The aim of this position statement is to provide recommendations for Canadian healthcare professionals regarding the use of genome-wide sequencing (GWS) in the context of diagnostic testing of the fetus during pregnancy. This statement was developed to facilitate clinical translation of GWS as a prenatal diagnostic test and the development of best practices in Canada, but the applicability of this document is broader and aims to help professionals in other healthcare systems. Methods of statement development A multidisciplinary group was assembled to review existing literature on fetal GWS for genetic diagnosis in the context of suspected monogenic diseases and to make recommendations relevant to the Canadian context. The statement was circulated for comments to the Canadian College of Medical Geneticists (CCMG) membership-at-large and, following incorporation of feedback, approved by the CCMG Board of Directors on 19 February 2021. Results and conclusions The use of prenatal GWS is indicated for the investigation of multiple fetal anomalies. Its use in the context of isolated fetal anomaly should be guided by available resources and current evidence, which is continually changing. During pregnancy, GWS should be ordered by, or in collaboration with, a medical geneticist. It should be used following detailed phenotyping to interrogate known disease genes, preferably using a trio approach, following detailed fetal phenotyping. Testing should be done with an overall aim to help in the management of the pregnancy, delivery and postnatal care. It should be guided by personal utility of the test for the pregnant person and clinical utility for pregnancy and birth management, as outlined herein. Genetic counselling is crucial in making the parental decision an informed decision. Chromosomal microarray analysis should be completed in parallel or prior to GWS and should be preceded by Quantitative Fluorescent PCR (QF- PCR) for detection of common aneuploidies. In normal circumstances, only pathogenic and likely pathogenic variants with a high likelihood of being associated with the identified fetal anomalies should be reported. Reporting of secondary findings, defined as purposeful analysis of variants in a set of medically actionable genes, should not, by default, be performed in the prenatal context. Laboratories should only report incidental findings that reveal risk of a significant Mendelian condition during infancy and childhood. Should a laboratory have a policy for reporting incidental findings in medically actionable adult-onset conditions, they should only be reported with explicit opt- in consent signed by the tested individuals. Genetic counselling is crucial in disclosing the test results and the implications the results may have for the fetus. It should be emphasised that negative results do not rule out a genetic diagnosis nor guarantee a good prognosis. Postnatal phenotyping and reanalysis of existing data should be considered. Families should be given the opportunity to participate in research studies as appropriate. These recommendations will be routinely re-evaluated as knowledge of the diagnostic and clinical utility of fetal GWS during pregnancy improves. [ABSTRACT FROM AUTHOR]

Non-invasive prenatal testing requires the presence of fetal DNA in maternal plasma. Understanding how preexamination conditions affect the integrity of cell-free DNA (cfDNA) and fetal fraction (FF) are a prerequisite for test implementation. Therefore, we examined the adjusted effect that EDTA and Streck tubes have on the cfDNA quantity and FF. A total of 3,568 maternal blood samples across Canada were collected in either EDTA, or Streck tubes, and processing metrics, maternal body mass index (BMI), gestational age and fetal karyotype and sex were recorded. Plasma samples were sequenced using two different sequencing platforms in separate laboratories. Sequencing data were processed with SeqFF to estimate FF. Linear regression and multivariate imputation by chained equations were used to estimate the adjusted effect of tube type on cfDNA and FF. We found a positive association between cfDNA quantity and blood shipment time in EDTA tubes, which is significantly reduced with the use of Streck tubes. Furthermore, we show the storage of plasma at −80 °C is associated with a 4.4% annual relative decrease in cfDNA levels. FF was not associated with collection tube type when controlling for confounding variables. However, FF was positively associated with gestational age and trisomy 21, while negatively associated with BMI, male fetus, trisomy 18, Turners syndrome and triploidy. Preexamination, maternal and fetal variables are associated with cfDNA quantity and FF. The consideration of these variables in future studies may help to reduce the number of pregnant women with inconclusive tests as a result of low FF. [ABSTRACT FROM AUTHOR]

Full coverage of the cost of clinical genetic testing is not always available through public or private insurance programs, or a public healthcare system. Consequently, some patients may be faced with the decision of whether to finance testing out‐of‐pocket (OOP), meet OOP expenses required by their insurer, or not proceed with testing. A scoping review was conducted to identify literature associated with patient OOP and private pay in clinical genetic testing. Seven databases (EMBASE, MEDLINE, CINAHL, PsychINFO, PAIS, the Cochrane Database of Systematic Reviews, and the JBI Evidence‐Based Practice database) were searched, resulting in 83 unique publications included in the review. The presented evidence includes a descriptive analysis, followed by a narrative account of the extracted data. Results were divided into four groups according to clinical indication: (1) hereditary breast and ovarian cancer, (2) other hereditary cancers, (3) prenatal testing, (4) other clinical indications. The majority of studies focused on hereditary cancer and prenatal genetic testing. Overall trends indicated that OOP costs have fallen and payer coverage has improved, but OOP expenses continue to present a barrier to patients who do not qualify for full coverage. [ABSTRACT FROM AUTHOR]

Non‐invasive prenatal testing (NIPT) based on analysis of cell free DNA circulating in the maternal plasma has been available clinically to screen for chromosomal abnormalities since 2011. There is significant evidence to suggest that NIPT has revolutionised prenatal screening for the common trisomies 13, 18, and 21. However, the evidence in favour of its extended use to screen for conditions other than these trisomies remains a topic of debate with no national or international organisation supporting clinical implementation for these indications. In the debate presented here – "Expanded NIPT that includes conditions other than trisomies 13, 18, and 21 should be offered" – we will see the pros and cons of screening for a wider range of chromosomal problems. The discussion presented swung the vote from 65% in favour and 35% against before the arguments were voiced to 41% in favour and 59% against. This significant swing in the vote indicates that the majority of our community feel more evidence is required before clinical implementation of extended NIPT. Key Points: What's already known about the topic? Non‐invasive prenatal testing (NIPT) is recognised as a highly efficient screening test for trisomy 21, trisomy 18, and trisomy 13 which has been implemented worldwide.The sensitivity, specificity, and positive predictive value (PPV) of cell free DNA for these three trisomies and sex chromosome anomalies are well described in the peer‐reviewed medical literature, but there is less evidence on performance or clinical utility when screening for other chromosomal anomalies or rare autosomal trisomies.There remains debate on whether expanded NIPT that includes conditions other than trisomies 13,18 and 21 should be offered. What does this study add? This report summarises the debate presented during the International Society of Prenatal Diagnosis virtual educational series in October 2020.Through the debate, the benefits, limitations, and challenges of offering expanded NIPT that includes screening for microdeletions, sex chromosome anomalies and rare autosomal trisomies was reviewed and discussed.At the end of the debate the audience was divided but the majority did not agree with offering expanded NIPT. [ABSTRACT FROM AUTHOR]