How do geneticists and prospective parents interpret and negotiate an uncertain prenatal genetic result? An analysis of clinical interactions

A decade of change - lessons learned from prenatal diagnostics in Central Denmark region in 2008-2018

INTRODUCTION

In 2011, it was decided to implement chromosomal microarray in prenatal testing in the Central Denmark Region, mainly due to the expected higher diagnostic yield. Chromosomal microarray was introduced gradually for an increasing number of pregnancies and without a transition period where both karyotyping and chromosomal microarray were performed: first malformations (2011), then large nuchal translucency (2013), then high risk at combined first trimester risk screening (2016) and finally for all indications (2018). This retrospective study summarizes 11 years of using chromosomal microarray in invasive prenatal testing and presents the effect on diagnostic yield and turnaround time. Furthermore, the concerns when introducing chromosomal microarray are presented and discussed.

MATERIAL AND METHODS

Registry data from the Danish Fetal Medicine Database, the regional fetal medicine database, the Danish Cytogenetic Central Register and the local laboratory database at Department of Clinical Genetics were all combined, and a cohort of 147 158 singleton pregnancies with at least one ultrasound examination was established RESULTS: Of the 147 158 pregnancies, invasive sampling was performed (chorionic villi or amniocytes) in 8456, corresponding to an overall invasive rate of 5.8%. Between 2016 and 2018, 3.4% (95% confidence interval [CI] 2.8-4.2%; n = 86) of the invasive samples (n = 2533) had a disease causing copy number variant and 5.3% (95% CI 4.4-6.2%; n = 133) had trisomies and other aneuploidies. The turnaround time more than halved from 14 days to an average of 5.5 days for chorionic villus sampling.

CONCLUSIONS

Chromosomal microarray identified 5.3% trisomies and 3.4% copy number variants, thereby increased the diagnostic yield by more than 64% compared with karyotype only and it also more than halved the turnaround time. Some preliminary concerns proved real, eg prenatal counseling complexity, but these have been resolved over time in a clinical path with expert consultations.

The role of a multidisciplinary team in managing variants of uncertain clinical significance in prenatal genetic diagnosis

BACKGROUND

Although in general prenatal exome sequencing only reports (likely) pathogenic variants, in some cases a variant of uncertain significance (VUS) is disclosed. The aims of this retrospective study were to evaluate the types of VUS that have been reported to prospective parents, possible reclassification and to design a standard flow chart to determine which types of VUS could be considered for reporting in prenatal settings. Furthermore, we investigated what the crucial elements are to facilitate rapid management of uncertain results in a prenatal setting.

MATERIAL AND METHODS

We reviewed exome results from 451 pregnancies performed in 2019-2021. We analyzed which factors that were taken into account by the multidisciplinary team (MDT) contributed towards decision making on reporting VUS after prenatal exome sequencing.

RESULTS

In 9/451 (2%) pregnancies tested with exome sequencing using a broad panel analysis a VUS was reported. After birth 3/9 VUS could be reclassified to likely pathogenic variants based on new clinical follow up data. We considered reporting VUS in genes: 1) matching the fetal phenotype, 2) associated with a severe disorder when a functional test is available or 3) possibly associated with a disorder where early post-partum diagnosis and treatment are crucial for a better prognosis. Two flowcharts were designed to guide first the laboratory specialist and then the MDT in decisions on reporting VUS. The crucial elements that enabled timely decisions on VUS disclosure were regular meetings, appropriate expertise, professional connections with other experts and psychological safety within the MDT.

CONCLUSION

In this study three out of nine VUS could be re-classified as likely pathogenic after clinical follow-up. In order to protect pregnant couples from the burden of uncertain results, the genetic professionals have to take the responsibility to limit the reporting of VUS. This can be done not only by automated filtering of data, by following professional guidelines and by building standardized decision flows, but also by discussing individual cases considering personal situations and the involved disease and by sharing professional experience and responsibility in a multidisciplinary prenatal team setting.

Retrospective identification of prenatal fetal anomalies associated with diagnostic neonatal genomic sequencing results

OBJECTIVE

To determine which types of fetal anomalies are associated with postnatal diagnoses of genetic diseases by genomic sequencing and to assess how prenatal genomic sequencing could affect clinical management.

METHOD

This was a secondary analysis of the second Newborn Sequencing in Genomic Medicine and Public Health study that compared fetal imaging results in critically ill infants who had actionable versus negative postnatal genomic sequencing results.

RESULTS

Of 213 infants who received genomic sequencing, 80 had available prenatal ultrasounds. Twenty-one (26%) of these were found to have genetic diseases by genomic sequencing. Fourteen (67%) of the 21 with genetic diseases had suspected anomalies prenatally, compared with 33 (56%) of 59 with negative results. Among fetuses with suspected anomalies, genetic diseases were 4.5 times more common in those with multiple anomalies and 6.7 times more common in those with anomalies of the extremities compared to those with negative results. Had the genetic diseases been diagnosed prenatally, clinical management would have been altered in 13 of 14.

CONCLUSION

Critically ill infants with diagnostic genomic sequencing were more likely to have multiple anomalies and anomalies of the extremities on fetal imaging. Among almost all infants with suspected fetal anomalies and diagnostic genomic sequencing results, prenatal diagnosis would have likely altered clinical management.

Views of Israeli healthcare professionals regarding communication of genetic variants of uncertain significance to patients

While genomic medicine is becoming an important part of patient care with an ever‐increasing diagnostic yield, communicating variants of uncertain clinical significance (VUSs) remains a major challenge. We draw on qualitative analysis of semi‐structured interviews conducted in 2020 with 20 Israeli healthcare professionals and stakeholders involved in communicating the results of genome‐wide sequencing to patients. Respondents described four main strategies of communicating VUSs to patients: preparing the patient pre‐test for uncertainty; adapting the level of detail to the patient's needs; upgrading versus downgrading the VUS; and following up on the possible reclassification of VUSs. These strategies were expressed differently by physicians and genetic counselors, varying according to their specialty and perception of the patient's situation. We discuss the strategic management and communication of uncertain genomic test results with patients in the context of meeting patients' expectations and working toward genetic causality through genomic narration and designation.

Increased nuchal translucency after low-risk noninvasive prenatal testing: What should we tell prospective parents?

Three decades ago, the observation that first trimester fetuses with excess fluid accumulation at the back of the neck were more likely to be aneuploid, gave rise to a new era of prenatal screening. The nuchal translucency (NT) measurement in combination with serum biomarkers and maternal age, resulted in the first trimester combined screening (FTCS) program. The introduction of noninvasive prenatal testing (NIPT) over the past decade has introduced the option for parents to receive highly sensitive and specific screening information for common trisomy from as early as 10 weeks gestation, altering the traditional pathway FTCS pathway. The retention of the 11-13-week NT ultrasound remains important in the detection of structural anomalies; however, the optimal management of pregnancies with a low-risk NIPT result and an isolated increased NT measurement in an era of advanced genomic testing options is a new dilemma for clinicians. For parents, the prolonged period between the initial diagnosis in first trimester, and prognostic information at each successive stage of investigations up to 22-24 weeks, can be emotionally challenging. This article addresses the common questions from parents and clinicians as they navigate the uncertainty of having a fetus diagnosed with an increased NT after a low-risk NIPT result and presents suggested approaches to management.

How are uncertain prenatal genetic results perceived and managed two years after they were received? A qualitative interview study

Chromosomal microarray has considerably improved our ability to identify or dismiss genetic conditions in the unborn child. However, this detailed analysis also reveals copy number variants (CNVs) of unknown or uncertain significance, in which the specific child's prognosis can be difficult to predict. Little is known about the longer-term impacts of receiving an uncertain prenatal CNV result. Our qualitative study explored how such a result was perceived and managed in everyday life, 2 years after it was received. From an original sample of 16 couples, nine women participated in a semi-structured follow-up phone interview. Transcripts were analyzed using thematic analysis. The results show that these women did not perceive the CNV result to be a part of their everyday lives. They managed the CNV result by focusing on the child's positive development, by not sharing the CNV information in wider social networks, and by emphasizing parental values such as taking life as it comes, welcoming human variation, and accepting that dealing with a child's struggles is an inherent part of parenthood. Overall, the women expressed a positive attitude toward prenatal genetic information about serious disorders but considered 'their' CNV to be close to normal; several women suggested that such findings should not be reported. However, they also recognized the difficulties in making such decisions, given variable penetrance and that couples' definitions of 'serious' could vary significantly. The diagnostic process during pregnancy was remembered as being highly stressful, and many expressed a need for more control in a future pregnancy. Our study provides insight into how mothers reconfigure CNV results to fit their values and everyday lives. When delivering uncertain CNV results in a prenatal setting, genetics healthcare providers should present and discuss long-term coping strategies with expecting parents.