Genetics and public health: the experience of a reference center for diagnosis of 22q11.2 deletion in Brazil and suggestions for implementing genetic testing

A systematic review of geographical inequities for accessing clinical genomic and genetic services for non-cancer related rare disease

Place plays a significant role in our health. As genetic/genomic services evolve and are increasingly seen as mainstream, especially within the field of rare disease, it is important to ensure that where one lives does not impede access to genetic/genomic services. Our aim was to identify barriers and enablers of geographical equity in accessing clinical genomic or genetic services. We undertook a systematic review searching for articles relating to geographical access to genetic/genomic services for rare disease. Searching the databases Medline, EMBASE and PubMed returned 1803 papers. Screening led to the inclusion of 20 articles for data extraction. Using inductive thematic analysis, we identified four themes (i) Current service model design, (ii) Logistical issues facing clinicians and communities, (iii) Workforce capacity and capability and iv) Rural culture and consumer beliefs. Several themes were common to both rural and urban communities. However, many themes were exacerbated for rural populations due to a lack of clinician access to/relationships with genetic specialist staff, the need to provide more generalist services and a lack of genetic/genomic knowledge and skill. Additional barriers included long standing systemic service designs that are not fit for purpose due to historically ad hoc approaches to delivery of care. There were calls for needs assessments to clarify community needs. Enablers of geographically equitable care included the uptake of new innovative models of care and a call to raise both community and clinician knowledge and awareness to demystify the clinical offer from genetics/genomics services.

Brazil's Craniofacial Project: Different approaches on orofacial clefts and 22q11.2 deletion syndrome

This article reports the present situation of Brazilian health care in genetics for Orofacial Cleft (OFC) and 22q11.2 Deletions Syndrome (22q11.2 DS) based on research conducted by Brazil's Craniofacial Project (BCFP). Established in 2003, BCFP is a voluntary and cooperative network aiming to investigate the health care of people with these diseases and other craniofacial anomalies. The initiatives and research results are presented in four sections: (a) a comprehensive report of the Brazilian public health system in craniofacial genetics; (b) multicentric studies developed on OFC and 22q11.2 DS; (c) education strategies focused on addressing these conditions for both population and health-care professionals; and (d) the nosology through the Brazilian Database on Craniofacial Anomalies (BDCA). Since 2006, BDCA uses a standardized method with detailed clinical data collection, which allows for conducting studies on nosology, genotype-phenotype correlations, and natural history; data can also contribute to public policies. Currently, the BDCA stores data on 1,724 individuals, including 1,351 (78.36%) who were primarily admitted due to OFC and 373 (21.63%) with clinical suspicion of 22q11.2 DS. Chromosomal abnormalities/genomic imbalances were represented by 92/213 (43.19%) individuals with syndromic OFC, including 43 with 22q11.2 DS, which indicates the need for chromosomal microarray analysis in this group. The nosologic diversity reinforces that monitoring clinical is the best strategy for etiological investigation. BCFP's methodology has introduced the possibility of increasing scientific knowledge and genetic diagnosis of OFC and 22q11.2 DS to in turn improve health care and policies for this group of diseases.

Testing criteria for 22q11.2 deletion syndrome: preliminary results of a low cost strategy for public health

BACKGROUND

The clinical heterogeneity of the 22q11.2 Deletion Syndrome (22q11.2DS - OMIM, #188400 and #192430) is a universal challenge leading to diagnostic delay. The aim of this study was to evaluate a low cost strategy for the diagnosis of this condition based upon clinical criteria previously reported. Health professionals, who collected clinical data, from twelve centers were trained in those criteria, which were summed through an online application (CranFlow).

RESULTS

Clinical and laboratorial data of 347 individuals registered from 2008 to 2017 in the Brazilian Database on Craniofacial Anomalies/22q11.2 Deletion Syndrome, were reviewed. They were divided in two groups: (I) 168 individuals investigated before the definition of the criteria and (II) 179 individuals investigated after the criteria application. All of them were investigated for 22q11.2DS by Fluorescent in situ Hybridization (FISH) and/or Multiplex Ligation Probe-dependent Amplification (MLPA), detecting 98 cases with 22q11.2DS. Among the individuals with 22q11.2DS in Group II, 42/53 (79.25%) fulfilled the proposed criteria against 11/53 (20.75%) who did not fulfill them (p < .0001). The association of congenital heart diseases with high predictive value for 22q11.2DS and hypernasal voice were significantly associated to the presence of 22q11.2DS (p = 0.0172 and p < .0001, respectively). In addition, 22q11.2DS was confirmed 3.82 more times when the individuals fulfilled the proposed criteria. Of the 249 cases negative for the typical deletion in 22q11.2, Chromosomal Microarray Analysis (CMA) was performed in 132 individuals and detected pathogenic alterations at other genomic regions in 19 individuals, and variants of uncertain clinical significance in 31 cases.

CONCLUSIONS

Therefore, a locus-specific approach could be used to individuals with positive criteria as a cost-effective alternative for 22q11.2DS diagnosis. The authors discuss advantages and suggest ways of implementing this approach to investigate 22q11.2DS in a public health system.

Ethical, social, and cultural issues related to clinical genetic testing and counseling in low- and middle-income countries: a systematic review

PURPOSE

We performed a systematic review of the ethical, social, and cultural issues associated with delivery of genetic services in low- and middle-income countries (LMICs).

METHODS

We searched 11 databases for studies addressing ethical, social, and/or cultural issues associated with clinical genetic testing and/or counselling performed in LMICs. Narrative synthesis was employed to analyze findings, and resultant themes were mapped onto the social ecological model (PROSPERO #CRD42016042894).

RESULTS

After reviewing 13,308 articles, 192 met inclusion criteria. Nine themes emerged: (1) genetic counseling has a tendency of being directive, (2) genetic services have psychosocial consequences that require improved support, (3) medical genetics training is inadequate, (4) genetic services are difficult to access, (5) social determinants affect uptake and understanding of genetic services, (6) social stigma is often associated with genetic disease, (7) family values are at risk of disruption by genetic services, (8) religious principles pose barriers to acceptability and utilization of genetic services, and (9) cultural beliefs and practices influence uptake of information and understanding of genetic disease.

CONCLUSION

We identified a number of complex and interrelated ethical, cultural, and social issues with implications implications for further development of genetic services in LMICs.

Cardiovascular abnormalities in patients with oral cleft: a clinical-electrocardiographic-echocardiographic study

OBJECTIVES

The present study aims to describe the clinical, electrocardiographic, and echocardiographic cardiological findings in a group of patients with oral clefts.

METHODS

This is a prospective cross-sectional study on 70 children (age range from 13 days to 19 years) with oral clefts who attended the multidisciplinary program of a university hospital from March 2013 to September 2014. The patients were evaluated by a pediatric cardiologist and underwent detailed anamnesis, physical examination, electrocardiogram, and echocardiogram.

RESULTS

Sixty percent of the patients were male; 55.7% presented with cleft lip and palate, and 40.0% presented with health complaints. Comorbidities were found in 44.3%. Relevant pregnancy, neonatal, family and personal antecedents were present in 55.7%, 27.1%, 67.2%, and 24.3% of the patients, respectively. Regarding the antecedents, 15.2% of the patients presented with a cardiac murmur, 49.0% with a familial risk of developing plurimetabolic syndrome, and 6% with family antecedents of rheumatic fever. Electrocardiographic evaluation showed one case of atrioventricular block. Echocardiograms were abnormal in 35.7% of the exams, including 5 cases of mitral valve prolapse - one of which was diagnosed with rheumatic heart disease.

CONCLUSION

The finding of a family risk of developing plurimetabolic syndrome and a diagnosis of rheumatic heart disease indicates that patients with oral clefts may be more prone to developing acquired heart disease. Thus, our findings highlight the importance of anamnesis and methodological triangulation (clinical-electrocardiographic-echocardiographic) in the investigation of patients with oral clefts and emphasize that cardiological follow-up to evaluate acquired and/or rhythm heart diseases is necessary. This strategy permits comorbidity prevention and individualized planned treatment.

Ethical, social, and cultural issues related to clinical genetic testing and counseling in low- and middle-income countries: protocol for a systematic review

BACKGROUND

There has been little focus in the literature on how to build genetic testing and counseling services in low- and middle-income countries in a responsible, ethical, and culturally appropriate manner. It is unclear to what extent this area is being explored and what form further research should take. The proposed knowledge synthesis aims to fill this gap in knowledge and mine the existing data to determine the breadth of work in this area and identify ethical, social, and cultural issues that have emerged.

METHODS/DESIGN

An integrated knowledge translation approach will be undertaken by engaging knowledge users throughout the review to ensure relevance to their practice. Electronic databases encompassing various disciplines, such as healthcare, social sciences, and public health, will be searched. Studies that address clinical genetic testing and/or counseling and ethical, social, and/or cultural issues of these genetic services, and are performed in low- and middle-income countries as defined by World Bank will be considered for inclusion. Two independent reviewers will be involved in a two-stage literature screening process, data extraction, and quality appraisal. Studies included in the review will be analyzed by thematic analysis. A narrative synthesis guided by the social ecological model will be used to summarize findings.

DISCUSSION

This systematic review will provide a foundation of evidence regarding ethical, social, and cultural issues related to clinical genetic testing and counseling in low- and middle-income countries. Using the social ecological model as a conceptual framework will facilitate the understanding of broader influences of the sociocultural context on an individual's experience with clinical genetic testing and counseling, thereby informing interdisciplinary sectors in future recommendations for practice and policy.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42016042894.

Diagnostic Approach to Microdeletion Syndromes Based on 22q11.2 Investigation: Challenges in Four Cases

In the last few decades, different methods for the detection of genomic imbalances, such as the microdeletion syndromes, were developed. The 22q11.2 deletion syndrome (22q11.2DS) is the most common microdeletion syndrome and presents wide clinical heterogeneity. The aim of this study was to describe 4 unusual cases of genomic imbalances found in individuals with suspected microdeletion syndromes. Different methods were necessary to complete the diagnosis and to obtain information for genetic counseling. The study was retrospective and descriptive. From August 2014 to December 2015, 39 individuals were assessed using FISH and/or MLPA; in 15 cases, chromosomal microarray (CMA) analysis was carried out. Of 39 registered individuals, we found deletions in the 22q11.2 region in 10 individuals (8 individuals with 22q11.2DS and 2 individuals presenting with atypical deletions in the 22q11.2 region: 1 distal deletion and 1 central deletion). In one case with a typical 22q11.2 deletion, a familial balanced translocation was detected. In another case without a 22q11.2 deletion, a 6p duplication concomitant with a 9p deletion was detected by CMA. Clinical data are reported and diagnostic investigations are discussed. Essential aspects for the understanding of different diagnostic techniques of genomic imbalances are considered, and the 4 cases described underline the complexity and the difficulties involved in the diagnostic process. The approach is informative for clinical practice and may be applied in other contexts of genomic imbalance investigation in microdeletion syndromes.

22q11.2 Deletion Syndrome: Laboratory Diagnosis and TBX1 and FGF8 Mutation Screening

Velocardiofacial syndrome is one of the recognized forms of chromosome 22q11.2 deletion syndrome (22q11.2 DS) and has an incidence of 1 of 4,000 to 1 of 6,000 births. Nevertheless, the 22q11 deletion is not found in several patients with a 22q11.2 DS phenotype. In this situation, other chromosomal aberrations and/or mutations in the T-box 1 transcription factor C (TBX1) gene have been detected in some patients. A similar phenotype to that of the 22q11.2 DS has been reported in animal models with mutations in fibroblast growth factor 8 (Fgf8) gene. To date, FGF8 mutations have not been investigated in humans. We tested a strategy to perform laboratory testing to reduce costs in the investigation of patients presenting with the 22q11.2 DS phenotype. A total of 109 individuals with clinical suspicion were investigated using GTG-banding karyotype, fluorescence in situ hybridization, and/or multiplex ligation-dependent probe amplification. A conclusive diagnosis was achieved in 33 of 109 (30.2%) cases. In addition, mutations in the coding regions of TBX1 and FGF8 genes were investigated in selected cases where 22q11.2 deletion had been excluded, and no pathogenic mutations were detected in both genes. This study presents a strategy for molecular genetic characterization of patients presenting with the 22q11.2 DS using different laboratory techniques. This strategy could be useful in different countries, according to local resources. Also, to our knowledge, this is the first investigation of FGF8 gene in humans with this clinical suspicion.

Costs of genetic testing: Supporting Brazilian Public Policies for the incorporating of molecular diagnostic technologies

This study identifies and describes the operating costs associated with the molecular diagnosis of diseases, such as hereditary cancer. To approximate the costs associated with these tests, data informed by Standard Operating Procedures for various techniques was collected from hospital software and a survey of market prices. Costs were established for four scenarios of capacity utilization to represent the possibility of suboptimal use in research laboratories. Cost description was based on a single site. The results show that only one technique was not impacted by rising costs due to underutilized capacity. Several common techniques were considerably more expensive at 30% capacity, including polymerase chain reaction (180%), microsatellite instability analysis (181%), gene rearrangement analysis by multiplex ligation probe amplification (412%), non-labeled sequencing (173%), and quantitation of nucleic acids (169%). These findings should be relevant for the definition of public policies and suggest that investment of public funds in the establishment of centralized diagnostic research centers would reduce costs to the Public Health System.

Clinical Features in Patients With 22q11.2 Deletion Syndrome Ascertained by Palatal Abnormalities

OBJECTIVES

The aim of this study was to describe clinical features in subjects with palatal abnormalities and to assess the distribution of these features among those with and without 22q11.2 deletion.

DESIGN

Descriptive cohort.

PATIENTS

One hundred patients with palatal abnormalities and suspicion of 22q11.2 DS were included.

METHODS

All patients were evaluated by a clinical geneticist, who completed a standardized clinical protocol. The 22q11.2 deletion screening was performed with fluorescence in situ hybridization using the TUPLE1 probe and multiplex ligation-dependent probe amplification using the P250-A1 kit.

RESULTS

The 22q11.2 deletion was detected in 35 patients, in whom the most frequent clinical features were congenital heart disease (15/30 - 50%), developmental delay (19/35 - 54%), speech delay (20/35 - 57%), learning disabilities (27/35 - 77%), immunologic alterations (18/29 - 62%). In addition, the most common facial dysmorphisms in this group were long face (27/35 - 77%), typical nose (24/35 - 69%), and hooded eyelids (19/35 - 54%). Comparing features in patients with or without the deletion revealed significant differences (positively correlated with the deletion) for speech delay, learning disabilities, conductive hearing loss, number of dysmorphisms, long face, and hooded eyelids. Cleft lip and palate was negatively correlated with the deletion.

CONCLUSIONS

The presence of speech delay, learning disabilities, conductive hearing loss, long face, and hooded eyelids should reinforce the suspicion of 22q11.2 DS in patients with palatal abnormalities and would help professionals direct clinical follow-up of these patients.