Genomic analysis in the clinic: benefits and challenges for health care professionals and patients in Brazil

The role of the Latin American Professional Society of Genetic Counseling (SPLAGen): Advancing genetic counseling in Latin America

The increasing importance of genomics and its expanding clinical application underscore the significance of genetic counseling in disseminating this vital information. In many countries, including regions of Latin America and the Caribbean, there is a shortage of adequately trained genetics providers thus limiting access to these essential services. Moreover, providers practicing genetic counseling are scarce and experience a lack of professional support. To address these challenges, the Latin American Professional Society of Genetic Counseling (SPLAGen, for its Spanish and Portuguese abbreviation) was established with the objective to increase awareness of and access to genetic counseling services in the region. Through this commentary, we aim to provide insights into the formation and organizational structure of SPLAGen, outlining our impactful work, as well as the current and future obstacles we foresee in our endeavor. SPLAGen's efforts aim to serve as a critical step toward bridging the gap in genetic counseling services and promoting better health care outcomes for patients living in Latin America and the Caribbean.

Assessment of medical knowledge toward genetic testing for individuals with hereditary breast and ovarian cancer syndrome in Brazil

Genetic testing has become increasingly used in medical practice to enable genetic cancer risk assessment. In Hereditary Breast and Ovarian Cancer syndrome (HBOC), it can be used to screen pathogenic germline variants. The access to early diagnosis, from the request until the proper interpretation of genetic tests depends on medical knowledge. The aim of this study was to evaluate the knowledge of family physicians, oncologists, geneticists and gynecologists regarding genetic testing for patients with suspected HBOC in Brazil. A cross-sectional survey of physicians was performed using a self-administered questionnaire. One hundred and ninety-two physicians answered the questionnaire (23 were geneticists, 38 gynecologists, 39 family physicians, and 92 oncologists). Only 15.4% of family physicians and 26% of gynecologists feel prepared to order genetic testing for patients with personal and/or family history of breast and/or ovarian cancer. Even though 87% of the oncologists have genetic testing available in their clinical practice, only 51.1% consider they have sufficient knowledge to manage patients after detecting a pathogenic germline variant and 17.4% do not feel comfortable interpreting them. Most oncologists and geneticists are very knowledgeable about recommendations for genetic testing order and management of HBOC patients. On the other hand, gynecologists and family physicians order genetic testing less frequently (28.9% and 7.7%, respectively) and have difficulties interpreting (26.3% and 2.3%, respectively) and managing these patients. These observations raise important issues regarding the implementation of genetic testing in Brazil, including the development of training programs for physicians from different specialties.

Familial history and prevalence of BRCA1, BRCA2 and TP53 pathogenic variants in HBOC Brazilian patients from a public healthcare service

Several studies have demonstrated the cost-effectiveness of genetic testing for surveillance and treatment of carriers of germline pathogenic variants associated with hereditary breast/ovarian cancer syndrome (HBOC). In Brazil, seventy percent of the population is assisted by the public Unified Health System (SUS), where genetic testing is still unavailable. And few studies were performed regarding the prevalence of HBOC pathogenic variants in this context. Here, we estimated the prevalence of germline pathogenic variants in BRCA1, BRCA2 and TP53 genes in Brazilian patients suspected of HBOC and referred to public healthcare service. Predictive power of risk prediction models for detecting mutation carriers was also evaluated. We found that 41 out of 257 tested patients (15.9%) were carriers of pathogenic variants in the analyzed genes. Most frequent pathogenic variant was the founder Brazilian mutation TP53 c.1010G > A (p.Arg337His), adding to the accumulated evidence that supports inclusion of TP53 in routine testing of Brazilian HBOC patients. Surprisingly, BRCA1 c.5266dupC (p.Gln1756fs), a frequently reported pathogenic variant in Brazilian HBOC patients, was not observed. Regarding the use of predictive models, we found that familial history of cancer might be used to improve selection or prioritization of patients for genetic testing, especially in a context of limited resources.

Medical geneticists, genetic diseases and services in Brazil in the age of personalized medicine

Aim: In anticipation of the implementation of personalized medicine in Brazil the authors assessed the characteristics of its medical genetics workforce together with the distribution of genetic diseases and services across the country. Materials & methods: The authors used demographic data on medical specialties, and summarized data from the public and private healthcare systems on live births, hospitalization and mortality, for the years 2019 and 2020. Results: The distribution of medical geneticists (MGs) overlapped the country-wide distribution of genetic diseases and services examined, indicating that ∼30% of the patient population has access to a MG specialist. Graduate specialism in medical genetics, registered MGs and suitable workplaces were concentrated in the south and southeast regions, leaving the north and northeast deeply underserved. Conclusion: MGs are concentrated in the wealthiest and most populated areas, while other regions have very limited services. These inequalities should be addressed for a successful transition to personalized medicine.

Using Online Mendelian Inheritance in Man in low- and middle-income countries

Online Mendelian Inheritance in Man (OMIM®), an online catalog of human genes and genetic disorders, has been used in the low- and middle-income countries largely as a tool for improving clinical care, teaching genetics and genomics, and for clinical and research analysis of next-generation sequencing. By facilitating free access to curated, updated, and comprehensive information in genetics and genomics, OMIM has led to better clinical care and research advancement in countries where clinicians and researchers in private or public hospitals and universities cannot afford to pay for other resources including journal subscriptions.

Economic Modelling of Screen-and-Treat Strategies for Brazilian Women at Risk of Hereditary Breast and Ovarian Cancer

BACKGROUND

Clinical evidence supports the use of genetic counselling and BRCA1/2 testing for women at risk for hereditary breast and ovarian cancer. Currently, screen-and-treat strategies are not reimbursed in the Brazilian Unified Healthcare System (SUS). The aim of this modelling study was to evaluate the cost effectiveness of a gene-based screen-and-treat strategy for BRCA1/2 in women with a high familial risk followed by preventive interventions compared with no screening.

METHODS

Adopting the SUS perspective, a Markov model with a lifelong time horizon was developed for a cohort of healthy women aged 30 years that fulfilled the criteria for BRCA1/2 testing according to the National Comprehensive Cancer Network (NCCN) guideline. For women who tested positive, preventive options included intensified surveillance, risk-reducing bilateral mastectomy and bilateral salpingo-oophorectomy. The Markov model comprised the health states 'well', 'breast cancer', 'death' and two post-cancer states. Outcomes were the incremental costs per quality-adjusted life-year (QALY) and the incremental costs per life-year gained (LYG). Data were mainly obtained by a literature review. Deterministic and probabilistic sensitivity analyses were performed to assess the robustness of the results.

RESULTS

In the base case, the screen-and-treat strategy resulted in additional costs of 3515 Brazilian reais (R$) (US$1698) and a gain of 0.145 QALYs, compared with no screening. The incremental cost-effectiveness ratio (ICER) was R$24,263 (US$21,724) per QALY and R$27,258 (US$24,405) per LYG. Applying deterministic sensitivity analyses, the ICER was most sensitive to the probability of a positive test result and the discount rate. In the probabilistic sensitivity analysis, a willingness to pay of R$25,000 per QALY gained for the screen-and-treat strategy resulted in a probability of cost effectiveness of 80%.

CONCLUSION

Although there is no rigorous cost-effectiveness threshold in Brazil, the result of this cost-effectiveness analysis may support the inclusion of BRCA1/2 testing for women at high-risk of cancer in the SUS. The ICER calculated for the provision of genetic testing for BRCA1/2 approximates the cost-effectiveness threshold proposed by the World Health Organization (WHO) for low- and middle-income countries.

Precision Medicine for Lysosomal Disorders

Precision medicine (PM) is an emerging approach for disease treatment and prevention that accounts for the individual variability in the genes, environment, and lifestyle of each person. Lysosomal diseases (LDs) are a group of genetic metabolic disorders that include approximately 70 monogenic conditions caused by a defect in lysosomal function. LDs may result from primary lysosomal enzyme deficiencies or impairments in membrane-associated proteins, lysosomal enzyme activators, or modifiers that affect lysosomal function. LDs are heterogeneous disorders, and the phenotype of the affected individual depends on the type of substrate and where it accumulates, which may be impacted by the type of genetic change and residual enzymatic activity. LDs are individually rare, with a combined incidence of approximately 1:4000 individuals. Specific therapies are already available for several LDs, and many more are in development. Early identification may enable disease course prediction and a specific intervention, which is very important for clinical outcome. Driven by advances in omics technology, PM aims to provide the most appropriate management for each patient based on the disease susceptibility or treatment response predictions for specific subgroups. In this review, we focused on the emerging diagnostic technologies that may help to optimize the management of each LD patient and the therapeutic options available, as well as in clinical developments that enable customized approaches to be selected for each subject, according to the principles of PM.

Diagnosis of Mucopolysaccharidoses

The mucopolysaccharidoses (MPSs) include 11 different conditions caused by specific enzyme deficiencies in the degradation pathway of glycosaminoglycans (GAGs). Although most MPS types present increased levels of GAGs in tissues, including blood and urine, diagnosis is challenging as specific enzyme assays are needed for the correct diagnosis. Enzyme assays are usually performed in blood, with some samples (as leukocytes) providing a final diagnosis, while others (such as dried blood spots) still being considered as screening methods. The identification of variants in the specific genes that encode each MPS-related enzyme is helpful for diagnosis confirmation (when needed), carrier detection, genetic counseling, prenatal diagnosis (preferably in combination with enzyme assays) and phenotype prediction. Although the usual diagnostic flow in high-risk patients starts with the measurement of urinary GAGs, it continues with specific enzyme assays and is completed with mutation identification; there is a growing trend to have genotype-based investigations performed at the beginning of the investigation. In such cases, confirmation of pathogenicity of the variants identified should be confirmed by measurement of enzyme activity and/or identification and/or quantification of GAG species. As there is a growing number of countries performing newborn screening for MPS diseases, the investigation of a low enzyme activity by the measurement of GAG species concentration and identification of gene mutations in the same DBS sample is recommended before the suspicion of MPS is taken to the family. With specific therapies already available for most MPS patients, and with clinical trials in progress for many conditions, the specific diagnosis of MPS as early as possible is becoming increasingly necessary. In this review, we describe traditional and the most up to date diagnostic methods for mucopolysaccharidoses.

'Omics Approaches to Explore the Breast Cancer Landscape

Breast cancer incidence is increasing worldwide with more than 600,000 deaths reported in 2018 alone. In current practice treatment options for breast cancer patients consists of surgery, chemotherapy, radiotherapy or targeting of classical markers of breast cancer subtype: estrogen receptor (ER) and HER2. However, these treatments fail to prevent recurrence and metastasis. Improved understanding of breast cancer and metastasis biology will help uncover novel biomarkers and therapeutic opportunities to improve patient stratification and treatment. We will first provide an overview of current methods and models used to study breast cancer biology, focusing on 2D and 3D cell culture, including organoids, and on in vivo models such as the MMTV mouse model and patient-derived xenografts (PDX). Next, genomic, transcriptomic, and proteomic approaches and their integration will be considered in the context of breast cancer susceptibility, breast cancer drivers, and therapeutic response and resistance to treatment. Finally, we will discuss how 'Omics datasets in combination with traditional breast cancer models are useful for generating insights into breast cancer biology, for suggesting individual treatments in precision oncology, and for creating data repositories to undergo further meta-analysis. System biology has the potential to catalyze the next great leap forward in treatment options for breast cancer patients.

From ‘Me’ to ‘Us’: solidarity and biocitizenship in the Brazilian cancer precision medicine innovation system

ABSTRACT As biotechnology innovations move from the bench to the bedside and, recently, also to the Internet, a myriad of emanating challenges and potentials may rise under distinct sociocultural and political economic contexts. Using a grounded-theory-inspired case study focused on the Brazilian research consortium for Medullary Endocrine Neoplasia type 2 (BrasMEN) – an inherited syndrome where genetic tests define cost-effective interventions – we outline facilitators and barriers to both development and implementation of a ‘public health genomics’ strategy under a developing country scenario. The study is based on participant observation at three centres and interviews with all who might hold an interest in MEN2 around Brazil. We discuss how a ‘solidarity’-based motivation for individual and collective ‘biocitizenship’ is driving people’s pre-emptive actions for accessing and making personalised healthcare available at Brazil’s Unified Health System (SUS) via the ‘co-production’ of science, technology and the culture for precision medicine – termed Brazil’s ‘hidden’ biomedical innovation system. Given the establishment of BrasMEN as ‘solidarity networks’ – promoting and supporting the cancer precision medicine’s rationale – our data illustrates how a series of new bioethical challenges raise from such engagement with familial cancer genomics under Brazil’s developing country scenario and how this social/soft technology constitute a solution for Euro/North American societies.

Fostering caring relationships: Suggestions to rethink liberal perspectives on the ethics of newborn screening

Newborn screening (NBS) involves the collection of blood from the heel of a newborn baby and testing it for a list of rare and inheritable disorders. New biochemical screening technologies led to expansions of NBS programs in the first decade of the 21st century. It is expected that they will in time be replaced by genetic sequencing technologies. These developments have raised a lot of ethical debate. We reviewed the ethical literature on NBS, analyzed the issues and values that emerged, and paid particular interest to the type of impacts authors think NBS should have on the lives of children and their families. Our review shows that most authors keep their ethical reflection confined to policy decisions, about for instance (a) the purpose of the program, and (b) its voluntary or mandatory nature. While some authors show appreciation of how NBS information empowers parents to care for their (diseased) children, most authors consider these aspects to be 'private' and leave their evaluation up to parents themselves. While this division of moral labor fits with the liberal conviction to leave individuals free to decide how they want to live their private lives, it also silences the ethical debate about these issues. Given the present and future capacity of NBS to offer an abundance of health-related information, we argue that there is good reason to develop a more substantive perspective to whether and how NBS can contribute to parents' good care for children.

BRCA1 and BRCA2 mutational profile and prevalence in hereditary breast and ovarian cancer (HBOC) probands from Southern Brazil: Are international testing criteria appropriate for this specific population?

Background

Germline pathogenic variants in BRCA1 and BRCA2 (BRCA) are the main cause of Hereditary Breast and Ovarian Cancer syndrome (HBOC).

Methods

In this study we evaluated the mutational profile and prevalence of BRCA pathogenic/likely pathogenic variants among probands fulfilling the NCCN HBOC testing criteria. We characterized the clinical profile of these individuals and explored the performance of international testing criteria.

Results

A pathogenic/likely pathogenic variant was detected in 19.1% of 418 probands, including seven novel frameshift variants. Variants of uncertain significance were found in 5.7% of individuals. We evaluated 50 testing criteria and mutation probability algorithms. There was a significant odds-ratio (OR) for mutation prediction (p ≤ 0.05) for 25 criteria; 14 of these had p ≤ 0.001. Using a cutoff point of four criteria, the sensitivity is 83.8%, and the specificity is 53.5% for being a carrier. The prevalence of pathogenic/likely pathogenic variants for each criterion ranged from 22.1% to 55.6%, and criteria with the highest ORs were those related to triple-negative breast cancer or ovarian cancer.

Conclusions

This is the largest study of comprehensive BRCA testing among Brazilians to date, and the first to analyze clinical criteria for genetic testing. Several criteria that are not included in the NCCN achieved a higher predictive value. Identification of the most informative criteria for each population will assist in the development of a rational approach to genetic testing, and will enable the prioritization of high-risk individuals as a first step towards offering testing in low-income countries.

Genetic education, knowledge and experiences between nurses and physicians in primary care in Brazil: A cross-sectional study

Recent advances in genomics and related technologies have the potential to improve health care throughout the world. In this cross-sectional study, we examine genetics education, knowledge, and genetics-related experiences among the nurses and physicians who provide primary care in a Brazilian city. Fifty-four healthcare professionals from family health units participated in the study (response rate: 90%). Data were collected using a structured 36-item questionnaire divided into five axes: sociodemographic data and academic background; genetics education; genetics knowledge; genetics-related experiences in family practice; and knowledge regarding the National Policy for Comprehensive Care in Clinical Genetics in the Unified Health System. Although most participants (85.2%) acknowledged receiving some genetic content during their undergraduate education, the majority (77.8%) advised that they did not feel prepared to deliver genomics-based health care in primary care. The results suggest that nurses and physicians often lack the knowledge to provide genomics-based health care in primary care. Therefore, continuing education in genetics/genomics should be provided to primary healthcare professionals in order to enhance family practice and compliance with national policies.