Ethical, legal and social implications of prenatal and preimplantation genetic testing for cancer susceptibility

Use of preimplantation genetic testing for monogenic adult-onset conditions: an Ethics Committee opinion

Preimplantation genetic testing for monogenic diseases for adult-onset conditions is ethically permissible for various conditions, including when the condition is fully penetrant or confers disease predisposition. The Committee strongly recommends that a genetic counselor experienced with both preimplantation genetic testing for monogenic diseases and assisted reproductive technology therapies counsel patients considering such procedures.

Mapping ethical, legal, and social implications (ELSI) of preimplantation genetic testing (PGT)

PURPOSE

Preimplantation Genetic Testing (PGT) has attracted considerable ethical, legal, and social scrutiny, but academic debate often fails to reflect clinical realities.

METHODS

Addressing this disconnect, a review of 506 articles from 1999 to 2019 across humanities and social sciences was conducted to synthesize the Ethical, Legal, and Social Implications (ELSI) of PGT. This review mined PubMed, WoS, and Scopus databases, using both MeSH terms and keywords to map out the research terrain.

RESULTS

The findings reveal a tenfold increase in global research output on PGT's ELSI from 1999 to 2019, signifying rising interest and concern. Despite heightened theoretical discourse on selecting "optimal" offspring, such practices were scarcely reported in clinical environments. Conversely, critical issues like PGT funding and familial impacts remain underexplored. Notably, 86% of the ELSI literature originates from just 12 countries, pointing to a research concentration.

CONCLUSION

This review underscores an urgent need for ELSI research to align more closely with clinical practice, promoting collaborations among ethicists, clinicians, policymakers, and economists. Such efforts are essential for grounding debates in practical relevance, ultimately steering PGT towards ethical integrity, societal acceptance, and equitable access, aiming to harmonize PGT research with real-world clinical concerns, enhancing the relevance and impact of future ethical discussions.

Development of a Predictive Model for Optimization of Embryo Transfer Timing Using Blood-Based microRNA Expression Profile

MicroRNAs (miRNAs) can regulate the expression of genes involved in the establishment of the window of implantation (WOI) in the endometrium. Recent studies indicated that cell-free miRNAs in uterine fluid and blood samples could act as alternative and non-invasive sample types for endometrial receptivity analysis. In this study, we attempt to systematically evaluate whether the expression levels of cell-free microRNAs in blood samples could be used as non-invasive biomarkers for assessing endometrial receptivity status. We profiled the miRNA expression levels of 111 blood samples using next-generation sequencing to establish a predictive model for the assessment of endometrial receptivity status. This model was validated with an independent dataset (n = 73). The overall accuracy is 95.9%. Specifically, we achieved accuracies of 95.9%, 95.9%, and 100.0% for the pre-receptive group, the receptive group, and the post-respective group, respectively. Additionally, we identified a set of differentially expressed miRNAs between different endometrial receptivity statuses using the following criteria: p-value < 0.05 and fold change greater than 1.5 or less than -1.5. In conclusion, the expression levels of cell-free miRNAs in blood samples can be utilized in a non-invasive manner to distinguish different endometrial receptivity statuses.

Molecular genetic testing strategies used in diagnostic flow for hereditary endocrine tumour syndromes

INTRODUCTION

Although current guidelines prefer the use of targeted testing or small-scale gene panels for identification of genetic susceptibility of hereditary endocrine tumour syndromes, next generation sequencing based strategies have been widely introduced into every day clinical practice. The application of next generation sequencing allows rapid testing of multiple genes in a cost effective manner. Increasing knowledge about these techniques and the demand from health care providers and society, shift the molecular genetic testing towards using high-throughput approaches.

PURPOSE

In this expert opinion, the authors consider the molecular diagnostic workflow step by step, evaluating options and challenges of gathering family information, pre- and post-test genetic counselling, technical and bioinformatical analysis related issues and difficulties in clinical interpretation focusing on molecular genetic testing of hereditary endocrine tumour syndromes.

RESULT AND CONCLUSION

Considering all these factors, a diagnostic genetic workflow is also proposed for selection of the best approach for testing of patients with hereditary genetic tumour syndromes in order to minimalize difficult interpretation, unwanted patient anxiety, unnecessary medical interventions and cost. There are potential benefits of utilizing high throughput approaches however, important limitations have to be considered and should discussed towards the clinicians and patients.

Structural Aberrations with Secondary Implications (SASIs): consensus recommendations for reporting of cancer susceptibility genes identified during analysis of Copy Number Variants (CNVs)

Clinical testing with chromosomal microarray (CMA) is most commonly undertaken for clinical indications such as intellectual disability, dysmorphic features and/or congenital abnormalities. Identification of a structural aberration (SA) involving a cancer susceptibility gene (CSG) constitutes a type of incidental or secondary finding. Laboratory reporting, risk communication and clinical management of these structural aberrations with secondary implications (SASIs) is currently inconsistent. We undertake meta-analysis of 18 622 instances of CMA performed for unrelated indications in which 106 SASIs are identified involving in total 40 different CSGs. Here we present the recommendations of a joint UK working group representing the British Society of Genomic Medicine, UK Cancer Genetics Group and UK Association for Clinical Genomic Science. SASIs are categorised into four groups, defined by the type of SA and the cancer risk. For each group, recommendations are provided regarding reflex parental testing and cancer risk management.

Key Ethical Issues in Prenatal Genetics: An Overview

The clinical integration of prenatal genetic technologies raises a series of important medical and ethical considerations for patients, families, health care providers, health care systems, and society. It is critical to recognize, understand, and address these issues in conjunction with the continued development of new prenatal genetic screens and tests. This article discusses some of the lead ethical issues as a starting point to further understanding their ramifications on patients, families, communities, and health care providers.

Uptake of prenatal diagnostic testing for retinoblastoma compared to other hereditary cancer syndromes in the Netherlands

Since the 1980s the genetic cause of many hereditary tumor syndromes has been elucidated. As a consequence, carriers of a deleterious mutation in these genes may opt for prenatal diagnoses (PND). We studied the uptake of prenatal diagnosis for five hereditary cancer syndromes in the Netherlands. Uptake for retinoblastoma (Rb) was compared with uptake for Von Hippel-Lindau disease (VHL), Li-Fraumeni syndrome (LFS), familial adenomatous polyposis (FAP), and hereditary breast ovarian cancer (HBOC). A questionnaire was completed by all nine DNA-diagnostic laboratories assessing the number of independent mutation-positive families identified from the start of diagnostic testing until May 2013, and the number of PNDs performed for these syndromes within these families. Of 187 families with a known Rb-gene mutation, 22 had performed PND (11.8%), this was significantly higher than uptake for FAP (1.6%) and HBOC (<0.2%). For VHL (6.5%) and LFS (4.9%) the difference was not statistically significant. PND for Rb started 3 years after introduction of diagnostic DNA testing and remained stable over the years. For the other cancer syndromes PND started 10-15 years after the introduction and uptake for PND showed an increase after 2009. We conclude that uptake of PND for Rb was significantly higher than for FAP and HBOC, but not different from VHL and LFS. Early onset, high penetrance, lack of preventive surgery and perceived burden of disease may explain these differences.

Assisted reproduction: Ethical and legal issues

Since inception, the use of assisted reproductive technologies (ART) has been accompanied by ethical, legal, and societal controversies. Guidelines have been developed to address many of these concerns; however, the rapid evolution of ART requires their frequent re-evaluation. We review the literature on ethical and legal aspects of ART, highlighting some of the most visible and challenging topics. Of specific interest are: reporting of ART procedures and outcomes; accessibility to ART procedures; issues related to fertility preservation, preimplantation genetic testing, gamete and embryo donation, and reproductive outcomes after embryo transfer. Improvements in ART reporting are needed nationally and worldwide. Reporting should include outcomes that enable patients to make informed decisions. Improving access to ART and optimizing long-term reproductive outcomes, while taking into account the legal and ethical consequences, are challenges that need to be addressed by the entire community of individuals involved in ART with the assistance of bioethicists, legal counselors, and members of society in general.

Breast cancer, BRCA mutations, and attitudes regarding pregnancy and preimplantation genetic diagnosis

BACKGROUND

Women with premenopausal breast cancer may face treatment-related infertility and have a higher likelihood of a BRCA mutation, which may affect their attitudes toward future childbearing.

METHODS

Premenopausal women were invited to participate in a questionnaire study administered before and after BRCA genetic testing. We used the Impact of Event Scale (IES) to evaluate the pre- and post-testing impact of cancer or carrying a BRCA mutation on attitudes toward future childbearing. The likelihood of pursuing prenatal diagnosis (PND) or preimplantation genetic diagnosis (PGD) was also assessed in this setting. Univariate analyses determined factors contributing to attitudes toward future childbearing and likelihood of PND or PGD.

RESULTS

One hundred forty-eight pretesting and 114 post-testing questionnaires were completed. Women with a personal history of breast cancer had less change in IES than those with no history of breast cancer (p = .003). The 18 BRCA-positive women had a greater change in IES than the BRCA-negative women (p = .005). After testing, 31% and 24% of women would use PND and PGD, respectively. BRCA results did not significantly affect attitudes toward PND/PGD.

CONCLUSION

BRCA results and history of breast cancer affect the psychological impact on future childbearing. Intentions to undergo PND or PGD do not appear to change after disclosure of BRCA results. Additional counseling for patients who have undergone BRCA testing may be warranted to educate patients about available fertility preservation options.

Preimplantation genetic diagnosis for inherited neurological disorders

Preimplantation genetic diagnosis (PGD) is an option for couples at risk of having offspring with an inherited debilitating or fatal neurological disorder who wish to conceive a healthy child. PGD has been carried out for conditions with various modes of inheritance, including spinal muscular atrophy, Huntington disease, fragile X syndrome, and chromosomal or mitochondrial disorders, and for susceptibility genes for cancers with nervous system involvement. Most couples at risk of transmitting a genetic mutation would opt for PGD over prenatal testing and possible termination of a pregnancy. The aim of this Perspectives article is to assist neurologists in counselling and treating patients who wish to explore the option of PGD to enable conception of an unaffected child. PGD can be accomplished for most disorders in which the genetic basis is known, and we argue that it is time for clinicians and neurological societies to consider the evidence and to formulate guidelines for the responsible integration of PGD into modern preventative neurology.

Incorporating information regarding preimplantation genetic diagnosis into discussions concerning testing and risk management for BRCA1/2 mutations: a qualitative study of patient preferences

BACKGROUND

Studies have shown that BRCA1/2 mutation carriers are interested in learning about reproductive options such as preimplantation genetic diagnosis (PGD) to prevent passing their risk onto their children. However, attitudes vary widely, and the procedure raises complex ethical and psychosocial issues. This complexity, plus the highly technical nature of PGD, makes it difficult to integrate PGD information into genetic counseling sessions that already cover probabilistic, emotionally charged risk information.

METHODS

A total of 33 carriers of the BRCA1/2 mutation who were of reproductive age and had previously undergone genetic counseling viewed a tutorial regarding PGD and were interviewed concerning their attitudes toward PGD and preferences about how to include PGD information in genetic counseling.

RESULTS

The majority of participants preferred to be briefly informed of the availability of PGD information, and to receive written materials regarding PGD, but with the option of deferring detailed discussion if they already believed themselves to be overloaded or perceived that PGD was not immediately relevant to their risk management and/or childbearing plans. For some individuals, the stress of testing temporarily interfered with information processing, producing states of cognitive avoidance ("in a fog," or "tuning out"). Some preferred to discuss PGD with a physician with whom they had an ongoing relationship (eg, obstetrician/gynecologist, primary care provider, or oncologist).

CONCLUSIONS

Providers offering cancer genetic testing may consider indicating the availability of PGD information to their patients, while attending to the patients' level of interest and ability to absorb information. Research is needed to link patient responses to information overload with psychosocial outcomes (eg, distress, and quality of decision-making). Continuing medical education is needed to support providers in facilitating informed decisions regarding PGD.

Breast cancer and fertility

OPINION STATEMENT

The increased availability of assisted reproductive technologies (ART) allows women with fertility issues to increase their chances of a successful pregnancy with the use of medications that, in some cases, increase circulating estrogens. There has been significant concern that the use of these medications will increase the risk of hormone-sensitive cancers such as breast, ovarian and uterine malignancies. Additionally, for those women who are diagnosed with a breast cancer during their reproductive years, this diagnosis can be particularly difficult as future fertility is a major concern for many young breast cancer survivors. With the current available data, there does not appear to be a statistically significant increase in the risk of developing breast cancer with ART, although several series suggest a potential possible related increase in borderline ovarian and uterine cancers. For breast cancer survivors, there does not appear to be an increased risk of death associated with subsequent pregnancies when compared with breast cancer patients who did not have subsequent pregnancies, although waiting at least 2 years after the diagnosis of breast cancer potentially may convey a protective effect. Therefore, when systemic therapy for breast cancer is recommended, early counseling and referral to a reproductive endocrinologist is warranted to provide optimal fertility preservation options. Further safety and outcomes studies are warranted for children.