Project description:The expanded use of NGS tests in genetic diagnosis enables the massive generation of data related to each individual, among which some findings are of medical value. Over the last three and a half years, 280 unrelated Lebanese patients, presenting a wide spectrum of genetic disorders were referred to our center for genetic evaluation by WES. Molecular diagnosis was established in 56% of the cases, as was previously reported. The current study evaluates secondary findings in these patients in 59 genes, linked to conditions mostly responsive to medical interventions, as per the ACMG guidelines. Our analysis allowed us to detect 19 pathogenic/likely pathogenic variants in 24 individuals from our cohort. Dominant actionable variants were found in 17 individuals representing 6% of the studied population. Genes associated with dominant cardiac diseases were the most frequently mutated: variants were found in 2.1% of our cohort. Genetic predisposition to cancer syndromes was observed in 1.07% of the cases. In parallel to dominant disease alleles, our analysis identified a recessive pathogenic disease allele in 2.5% of the individuals included in this study. Of interest, some variants were detected in different patients from our cohort thus urging the study of their prevalence in our population and the implementation, when needed, of specific genetic testing in the neonatal screening panel. In conclusion, here we report the first study estimating the actionable pathogenic variant load in the Lebanese population. Communicating current findings to the patients will enable them to benefit from a multi-disciplinary approach. Furthermore, tailoring the ACMG guidelines to the population is suggested, especially in highly consanguineous populations where the information related to recessive alleles might be highly beneficial to patients and their families.
Project description:Purpose: Discovering an incidental finding (IF) or secondary finding (SF) is a potential result of genomic testing, but few data exist describing types and frequencies of SFs likely to appear in broader clinical populations.Methods: The Electronic Medical Records and Genomics Network Phase III (eMERGE III) developed a CLIA-compliant sequencing panel of 109 genes and 1551 variants of clinical relevance or research interest and deployed this panel at ten clinical sites. We evaluated medically actionable SFs across 67 genes and 14 single-nucleotide variants (SNVs) in a diverse cohort of 21,915 participants drawn from a variety of settings (e.g., primary care, biobanks, specialty clinics).Results: Correcting for testing indication, we found a 3.02% overall frequency of SFs; 2.54% from 59 genes the American College of Medical Genetics and Genomics recommends for SF return, and 0.48% in other genes, primarily HFE and PALB2. SFs associated with cancer susceptibility were most frequent (1.38%), followed by cardiovascular diseases (0.87%), and lipid disorders (0.50%). After removing HFE, the frequency of SFs and proportion of pathogenic versus likely pathogenic SFs did not differ in those self-identifying as White versus others.Conclusion: Here we present frequencies and types of medically actionable secondary findings to support informed decision making by patients, participants, and practitioners engaged in genomic medicine.
Project description:BACKGROUND:The Personal Genome Project Canada is a comprehensive public data resource that integrates whole genome sequencing data and health information. We describe genomic variation identified in the initial recruitment cohort of 56 volunteers. METHODS:Volunteers were screened for eligibility and provided informed consent for open data sharing. Using blood DNA, we performed whole genome sequencing and identified all possible classes of DNA variants. A genetic counsellor explained the implication of the results to each participant. RESULTS:Whole genome sequencing of the first 56 participants identified 207 662 805 sequence variants and 27 494 copy number variations. We analyzed a prioritized disease-associated data set (n = 1606 variants) according to standardized guidelines, and interpreted 19 variants in 14 participants (25%) as having obvious health implications. Six of these variants (e.g., in BRCA1 or mosaic loss of an X chromosome) were pathogenic or likely pathogenic. Seven were risk factors for cancer, cardiovascular or neurobehavioural conditions. Four other variants - associated with cancer, cardiac or neurodegenerative phenotypes - remained of uncertain significance because of discrepancies among databases. We also identified a large structural chromosome aberration and a likely pathogenic mitochondrial variant. There were 172 recessive disease alleles (e.g., 5 individuals carried mutations for cystic fibrosis). Pharmacogenomics analyses revealed another 3.9 potentially relevant genotypes per individual. INTERPRETATION:Our analyses identified a spectrum of genetic variants with potential health impact in 25% of participants. When also considering recessive alleles and variants with potential pharmacologic relevance, all 56 participants had medically relevant findings. Although access is mostly limited to research, whole genome sequencing can provide specific and novel information with the potential of major impact for health care.
Project description:Liquid biopsies are increasingly used in the care of patients with advanced cancers. These tests are used to find mutations and other genomic alterations, quantify these findings over time, and guide treatment. It is not unexpected that germline mutations contributing to the development of cancer can be identified in cell-free DNA. Consequently, increased use of liquid biopsies has resulted in subsequent rise of secondary identification of germline mutations. Clinicians need to be aware of this potential use of liquid biopsies and the need to evaluate the patient and family members for confirmation. Our case documents a deceased patient's liquid biopsy result that was confirmed as a germline mutation through a methodical work-up of the patient's family members. Here, we present the case and provide a brief review of pertinent literature.
Project description:PURPOSE:Genomic sequencing can reveal variants with limited to no medical actionability. Previous research has assessed individuals' intentions to learn this information, but few report the decisions they made and why. METHODS:The North Carolina Clinical Genomic Evaluation by Next Generation Exome Sequencing (NCGENES) project evaluated adult patients randomized to learn up to six types of non-medically actionable secondary findings (NMASF). We previously found that most participants intended to request NMASF and intentions were strongly predicted by anticipated regret. Here we examine discrepancies between intentions and decisions to request NMASF, hypothesizing that anticipated regret would predict requests but that this association would be mediated by participants' intentions. RESULTS:Of the 76% who expressed intentions to learn results, only 42% made one or more requests. Overall, only 32% of the 155 eligible participants requested NMASF. Analyses support a plausible causal link between anticipated regret, intentions, and requests. CONCLUSIONS:The discordance between participants' expressed intentions and their actions provides insight into factors that influence patients' preferences for genomic information that has little to no actionability. These findings have implications for the timing and methods of eliciting preferences for NMASF and suggest that decisions to learn this information have cognitive and emotional components.
Project description:PURPOSE:Clinically relevant secondary variants were identified in parents enrolled with a child with developmental delay and intellectual disability. METHODS:Exome/genome sequencing and analysis of 789 "unaffected" parents was performed. RESULTS:Pathogenic/likely pathogenic variants were identified in 21 genes within 25 individuals (3.2%), with 11 (1.4%) participants harboring variation in a gene defined as clinically actionable by the American College of Medical Genetics and Genomics. These 25 individuals self-reported either relevant clinical diagnoses (5); relevant family history or symptoms (13); or no relevant family history, symptoms, or clinical diagnoses (7). A limited carrier screen was performed yielding 15 variants in 48 (6.1%) parents. Parents were also analyzed as mate pairs (n?=?365) to identify cases in which both parents were carriers for the same recessive disease, yielding three such cases (0.8%), two of which had children with the relevant recessive disease. Four participants had two findings (one carrier and one noncarrier variant). In total, 71 of the 789 enrolled parents (9.0%) received secondary findings. CONCLUSION:We provide an overview of the rates and types of clinically relevant secondary findings, which may be useful in the design and implementation of research and clinical sequencing efforts to identify such findings.
Project description:Whole exome/genome sequencing (WES/WGS) is increasingly offered to ostensibly healthy individuals. Understanding the motivations and concerns of research participants seeking out personal WGS and their preferences regarding return-of-results and data sharing will help optimize protocols for WES/WGS. Baseline interviews including both qualitative and quantitative components were conducted with research participants (n=35) in the HealthSeq project, a longitudinal cohort study of individuals receiving personal WGS results. Data sharing preferences were recorded during informed consent. In the qualitative interview component, the dominant motivations that emerged were obtaining personal disease risk information, satisfying curiosity, contributing to research, self-exploration and interest in ancestry, and the dominant concern was the potential psychological impact of the results. In the quantitative component, 57% endorsed concerns about privacy. Most wanted to receive all personal WGS results (94%) and their raw data (89%); a third (37%) consented to having their data shared to the Database of Genotypes and Phenotypes (dbGaP). Early adopters of personal WGS in the HealthSeq project express a variety of health- and non-health-related motivations. Almost all want all available findings, while also expressing concerns about the psychological impact and privacy of their results.
Project description:PurposeExome sequencing of a single individual for a clinical indication may result in the identification of incidental deleterious variants unrelated to the indication for testing (secondary findings). Given the recent availability of clinical exome testing, there is a limited knowledge regarding the disclosure preferences and impact of secondary findings in a clinical diagnostic setting. In this article, we provide preliminary data regarding the preferences for secondary findings results disclosure based on the first 200 families referred to Ambry Genetics for diagnostic exome sequencing.MethodsSecondary findings were categorized into four groups in the diagnostic exome sequencing consent: carrier status of recessive disorders, predisposition to later-onset disease, predisposition to increased cancer risk, and early-onset disease. In this study, we performed a retrospective analysis of patient responses regarding the preferences for secondary findings disclosure.ResultsThe majority of patients (187/200; 93.5%) chose to receive secondary results for one or more available categories. Adult probands were more likely than children to opt for blinding of secondary data (16 vs. 4%, respectively). Among responses for blinding, preferences were evenly scattered among categories.ConclusionThese data represent the unprecedented results of a large reference laboratory providing clinical exome sequencing. We report, for the first time, the preferences of patients and families for the receipt of secondary findings based on clinical genome sequencing. Overwhelmingly, families undergoing exome sequencing opt for the disclosure of secondary findings. The data may have implications regarding the development of guidelines for secondary findings reporting among patients with severe and/or life-threatening disease undergoing clinical genomic sequencing.
Project description:BackgroundData on the modalities of disclosing genomic secondary findings (SFs) remain scarce. We explore cancer patients' and the general public's perspectives about disclosing genomic SFs and the modalities of such disclosure.MethodsSixty-one cancer patients (n = 29) and members of the public (n = 32) participated in eight focus groups in Montreal and Quebec City, Canada. They were asked to provide their perspectives of five fictitious vignettes related to medically actionable and non-actionable SFs. Two researchers used a codification framework to conduct a thematic content analysis of the group discussion transcripts.ResultsCancer patients and members of the public were open to receive genomic SFs, considering their potential clinical and personal utility. They believed that the right to know or not and share or not such findings should remain the patient's decision. They thought that the disclosure of SFs should be made mainly in person by the prescribing clinician. Maintaining confidentiality when so requested and preventing genetic discrimination were considered essential.ConclusionParticipants in this study welcomed the prospect of disclosing genomic SFs, as long as the right to choose to know or not to know is preserved. They called for the development of policies and practice guidelines that aim to protect genetic information confidentiality as well as the autonomy, physical and psychosocial wellbeing of patients and families.