HLA-matched embryos selected for siblings requiring haematopoietic stem cell transplantation: a psychological perspective

A review on the motivations, decision-making factors, attitudes and experiences of couples using pre-implantation genetic testing for inherited conditions

BACKGROUND

In pre-implantation genetic testing (PGT), fertile couples undergo IVF with genetic testing of embryos to avoid conceptions with a genetic condition. There is an exponentially increasing uptake with over 600 applications listed by the Human Fertilisation and Embryology Authority in the UK. The psychological aspects of the decision-making process and the experience of PGT, however, are relatively underevaluated, with the potential to leave patients unsupported in their journeys.

OBJECTIVE AND RATIONALE

In this review, we aim to comprehensively report on every aspect of couples' experiences of PGT. We consider what motivates users, the practical and ethical decisions involved and how couples navigate the decision-making process. Additionally, we report on the social and psychological impact on couples who are actively undergoing or have completed the PGT process.

SEARCH METHODS

A systematic search of English peer-reviewed journals of three computerized databases was undertaken following PRISMA guidelines. Studies that examined the motivations, attitudes, decision-making factors and experiences of patients who have been actively engaged in the PGT process were included. No restrictions were placed on study design or date of publication. Studies examining patients using PGT in a hypothetical context or solely using PGT for aneuploidy were excluded. Qualitative data were extracted using thematic analysis.

OUTCOMES

The main outcomes were patient motivations, deciding factors and attitudes, as well as the patient experience of coming to a decision and going through PGT.Patients were primarily motivated by the desire to have a healthy child and to avoid termination of pregnancy. Those with a sick child or previous experience of termination were more likely to use PGT. Patients also felt compelled to make use of the technology available, either from a moral responsibility to do so or to avoid feelings of guilt if not. The main factors considered when deciding to use PGT were the need for IVF and the acceptability of the technology, the financial cost of the procedure and one's ethical standpoint on the creation and manipulation of embryos. There was a general consensus that PGT should be applied to lethal or severe childhood disease but less agreement on use for adult onset or variable expression conditions. There was an agreement that it should not be used to select for aesthetic traits and a frustration with the views of PGT in society. We report that couples find it difficult to consider all of the benefits and costs of PGT, resulting in ambivalence and prolonged indecision. After deciding on PGT use, we found that patients find the process extremely impractical and psychologically demanding.

WIDER IMPLICATIONS

This review aimed to summarize the current knowledge on how patients decide to use and experience PGT and to make suggestions to incorporate the findings into clinical practice. We cannot stress enough the importance of holistic evaluation of patients and thorough counselling prior to and during PGT use from a multidisciplinary team that includes geneticists, IVF clinicians, psychologists and also patient support groups. Large prospective studies using a validated psychological tool at various stages of the PGT process would provide an invaluable database for professionals to better aid patients in their decision-making and to improve the patient experience.

Preimplantation genetic testing with HLA matching: from counseling to birth and beyond

Preimplantation genetic testing-human leukocyte antigen '(PGT-HLA) only' refers to the HLA typing of single or few cells biopsied from in vitro fertilized preimplantation embryos. The aim of the procedure is to establish a pregnancy, in which the fetus is HLA compatible with an affected sibling in need of a hematopoietic stem cell transplantation (HSCT). During PGT-M-HLA, the identification of a HLA-compatible embryo is combined with the detection of mutation(s) underlying immunodeficiencies and hemoglobinopathies. We report a combined retrospective and prospective cohort analysis of PGT-(M-)HLA procedures carried out from 1998 until 2017, with follow-up of transplantations to 2019. During the study period, 234 couples from 22 countries were invited for a multidisciplinary consultation. Two couples were rejected and 70 couples declined (various reasons), leaving 162 couples for which 414 clinical cycles were carried out. Cleavage stage biopsy followed by single-cell multiplex PCR for short tandem repeat-based haplotyping was applied in most cases (98.7%). The diagnostic efficiency was high (94.8%) but only 16.5% of the embryos was genetically suitable for transfer. Fresh and frozen-thawed embryo transfer resulted in 67 clinical pregnancies, 63 deliveries, and 74 live births, of which 60 children were HLA compatible. This yielded a live birth delivery rate of 30.3% per transfer. Information on neonatal characteristics of the matching PGT-(M-)HLA children showed reassuring outcomes. So far, HSCT was carried out successfully for 25 out of 26 cases. In conclusion, our data show that PGT-(M-)HLA is a valuable procedure: the high complexity and limited delivery rate are balanced by the successful HSCT outcome and the positive impact on families.

Factors Influencing the Decision-Making Process and Long-Term Interpersonal Outcomes for Parents Who Undergo Preimplantation Genetic Diagnosis for Fanconi Anemia: a Qualitative Investigation

Fanconi anemia (FA) is characterized by congenital malformations, progressive bone marrow failure, and predisposition to malignancy. Hematopoietic stem cell transplantation is used to treat FA, and best results are attained with sibling donors who are human leukocyte antigen (HLA) identical matches. Preimplantation genetic diagnosis (PGD) offers parents of an affected child the opportunity to have an unaffected child who is an HLA match. While some research has investigated parents' experiences during the PGD process, no published studies specifically address factors influencing their decision-making process and long-term interpersonal outcomes. The aims of this study are to: (1) examine parents' expectations and the influence of media, bioethics, and religion on their decision to undergo PGD; (2) examine parents' social support and emotional experiences during their PGD process; and (3) characterize long-term effects of PGD on relationship dynamics (partner, family, friends), others' attitudes, and parental regret. Nine parents participated in semi-structured interviews. Thematic analysis revealed their decision to use PGD was variously influenced by media, bioethics, and religion, in particular, affecting parents' initial confidence levels. Moreover, the PGD process was emotionally complex, with parents desiring varying amounts and types of support from different sources at different times. Parents reported others' attitudes towards them were similar or no different than before PGD. Parental regret regarding PGD was negligible. Results of this study will promote optimization of long-term care for FA families.

PGD for monogenic disorders: aspects of molecular biology

Preimplantation genetic diagnosis (PGD) for monogenic diseases has known a considerable evolution since its first application in the early 1990s. Especially the technical aspects of the genetic diagnosis itself, the single-cell genetic analysis, has constantly evolved to reach levels of accuracy and efficiency nearing those of genetic diagnosis on regular DNA samples. In this review, we will focus on the molecular biological techniques that are currently in use in the most advanced centers for PGD for monogenic disorders, including multiplex polymerase chain reaction (PCR) and post-PCR diagnostic methods, whole genome amplification (WGA) and multiple displacement amplification (MDA). As it becomes more and more clear that when it comes to ethically difficult indications, PGD goes further than prenatal diagnosis (PND), we will also briefly discuss ethical issues.

First successful bone marrow transplantation for X-linked chronic granulomatous disease by using preimplantation female gender typing and HLA matching

Allogeneic hematopoietic stem cell transplantation from an human leukocyte antigen (HLA)-identical donor is currently the only proven curative treatment for chronic granulomatous disease. Hematopoietic stem cell transplantation with alternative donors is associated with higher morbidity and mortality. Therefore, we performed in vitro fertilization and preimplantation HLA matching combined with female sexing for hematopoietic stem cell transplantation in chronic granulomatous disease. Ethical and psychological issues were considered carefully. We used in vitro fertilization with X-enriched spermatozoa followed by preimplantation genetic diagnosis to identify female HLA-genoidentical embryos in a family in need of a suitable donor for their boy affected with severe X-linked chronic granulomatous disease. Two preimplantation genetic diagnosis cycles were performed in the family. In the second cycle, 2 HLA-genoidentical female embryos were transferred and a singleton pregnancy was obtained, resulting in the birth of an unaffected girl at term. Because of insufficient cell numbers in the cord-blood source, conventional hematopoietic stem cell transplantation had to be performed at 12 months of age of the donor and 5 years of age of the recipient and resulted in complete stable donor chimerism and immunologic reconstitution up to 25 months post-hematopoietic stem cell transplantation. Hematopoietic stem cell transplantation after in vitro fertilization and combined female sexing and HLA matching offers a new and relatively rapid therapeutic option for patients with X-linked primary immunodeficiency such as chronic granulomatous disease who need hematopoietic stem cell transplantation but lack an HLA-genoidentical donor.

Preimplantation genetic diagnosis: an overview of socio-ethical and legal considerations

Preimplantation genetic diagnosis (PGD) permits the selection of embryos of a particular genotype prior to implantation. As a reproductive technology involving embryo selection, PGD has become associated with considerable controversy. This review examines some of the ethical, legal, and social issues raised by PGD. Relevant ethical considerations include the status of the embryo and the interests and duties of the parents. On a social policy level, considerations of access as well as the impact of this technology on families, women, and physician's duties also warrant consideration. An analysis of these issues in the context of using PGD for selecting embryos unaffected by a serious disorder and for sex selection is presented. We also present a brief survey of PGD-related regulatory schemes in several countries, including the United Kingdom and the United States.

The future (r)evolution of preimplantation genetic diagnosis/human leukocyte antigen testing: ethical reflections

There has been increasing support for combining preimplantation genetic diagnosis (PGD) for specific diseases with a test for human leukocyte antigens (HLA) because the generation of HLA-matched umbilical cord blood cells may save the life of a diseased sibling. To date, this procedure has taken place in the context of conceiving another child--PGD/HLA testing type 1. However, it may well become possible to perform PGD/HLA testing outside this context, that is, to select matched embryos from which embryonic stem cells could be derived and used in cell therapy--PGD/HLA testing type 2. A proactive ethical analysis is needed and is presented in this article. Although PGD/HLA testing type 1 can be morally justified, the risks, pitfalls, and practical limitations of this procedure make it necessary to develop alternative strategies. PGD/HLA testing type 2 may provide an alternative strategy. From an ethical point of view, the controversial issue is that this procedure creates embryos purely for instrumental use. However, given the dominant view that the preimplantation embryo has only limited moral value, this alternative may be as morally justified as PGD/HLA testing type 1.

Le diagnostic préimplantatoire couplé au typage HLA : l'expérience parisienne

Preimplantation genetic diagnosis (PGD) consists in the genetic analysis of one or two cells. These cells (blastomeres) are sampled from embryos, obtained by in vitro fertilization, at the third day of development. Since 1998, the bioethical laws (1994) and their decrees restricted PGD practices in France, strictly to the avoidance of the birth of a child affected with a genetic defect. In parallel, works on blood cord transplantation, taken at the birth of a compatible HLA sibling, showed very encouraging results, particularly for the treatment of Fanconi anemia. In 2001, Verlinsky et al., have reported the first PGD for Fanconi anaemia combined with HLA typing, allowing the birth of a healthy child, HLA-identical with his affected sister. The "designer baby" concept was born. The French law, which allowed PGD under specific conditions, i.e. when the genetic defect has been characterized in one parent at least, recently extended PGD to HLA typing when embryos are at risk of a genetic disorder. Article L.2131-4-1 (August 2004) allows the practice of HLA typing for PGD embryos when an elder sibling is affected with a genetic disorder and need stem cell transplantation. The HLA-matched offspring resulting from PGD can give cord blood at birth to supply the necessary therapy. This double selection give rise to serious ethical problems, but technical difficulties and legal restrictions will probably limit the development of such a procedure.