Cardiac genetic test yields and genotype-phenotype correlations from large cohort investigated by medical examiner's office.

BACKGROUND: Few reports describe the yield of postmortem genetic testing from medical examiners' offices or correlate genetic test results with autopsy-confirmed phenotypes from a large cohort. OBJECTIVES: To report results from cardiomyopathy- and cardiac arrhythmia-associated genetic testing in conjunction with autopsy findings of cases investigated at the United States' largest medical examiner office. METHODS: Postmortem cases tested from 2015 to 2022 with a cardiomyopathy- and cardiac arrhythmia-associated gene panel were reviewed. American College of Medical Genetics and Genomics/Association for Molecular Pathology guidelines were used to classify variant pathogenicity. Correlations of pathogenic/likely pathogenic variants (P/LPVs) with cardiac pathology were evaluated. RESULTS: The cohort included 1107 decedents of diverse ages and ethnicities. P/LPVs were detected in 87 (7.9%) cases, with 73 and 14 variants in cardiomyopathy and cardiac arrhythmia genes, respectively. Variants of uncertain significance were detected in 437 (39.5%) cases. The diagnostic yield (percentage of P/LPV) in decedents with cardiomyopathy (26.1%) was significantly higher than those without (P<.0001). The diagnostic yield was significantly lower in infants (0.7%) than older age groups (ranging from 1 to 74 years old, 5.7%-25.9%), which had no statistical difference between their yields. The diagnostic yields by cardiac autopsy findings were 54.0% for hypertrophic cardiomyopathy, 47.1% for arrhythmogenic cardiomyopathy, 20.0% for myocardial fibrosis, 19.0% for dilated cardiomyopathy, and 11.3% for myocarditis. Most P/LPVs were in MYBPC3, TTN, PKP2, SCN5A, MYH7, and FLNC. Ten P/LPVs were novel. CONCLUSIONS: Our results support the importance of performing postmortem genetic testing on decedents of all ages with cardiomyopathy, cardiac lesions insufficient to diagnosis a specific cardiomyopathy (e.g., myocardial fibrosis), and myocarditis. Combined postmortem cardiac examination and genetic analysis are advantageous in accurately determining the underlying cause of death and informing effective clinical care of family members.

Researching COVID to enhance recovery (RECOVER) tissue pathology study protocol: Rationale, objectives, and design.

IMPORTANCE: SARS-CoV-2 infection can result in ongoing, relapsing, or new symptoms or organ dysfunction after the acute phase of infection, termed Post-Acute Sequelae of SARS-CoV-2 (PASC), or long COVID. The characteristics, prevalence, trajectory and mechanisms of PASC are poorly understood. The objectives of the Researching COVID to Enhance Recovery (RECOVER) tissue pathology study (RECOVER-Pathology) are to: (1) characterize prevalence and types of organ injury/disease and pathology occurring with PASC; (2) characterize the association of pathologic findings with clinical and other characteristics; (3) define the pathophysiology and mechanisms of PASC, and possible mediation via viral persistence; and (4) establish a post-mortem tissue biobank and post-mortem brain imaging biorepository. METHODS: RECOVER-Pathology is a cross-sectional study of decedents dying at least 15 days following initial SARS-CoV-2 infection. Eligible decedents must meet WHO criteria for suspected, probable, or confirmed infection and must be aged 18 years or more at the time of death. Enrollment occurs at 7 sites in four U.S. states and Washington, DC. Comprehensive autopsies are conducted according to a standardized protocol within 24 hours of death; tissue samples are sent to the PASC Biorepository for later analyses. Data on clinical history are collected from the medical records and/or next of kin. The primary study outcomes include an array of pathologic features organized by organ system. Causal inference methods will be employed to investigate associations between risk factors and pathologic outcomes. DISCUSSION: RECOVER-Pathology is the largest autopsy study addressing PASC among US adults. Results of this study are intended to elucidate mechanisms of organ injury and disease and enhance our understanding of the pathophysiology of PASC.

The next phase in patient safety education: Towards a standardized, tools-based pathology patient safety curriculum: A call to action from the Association of Pathology Chairs' Residency Program Directors Section Training Residents in Patient Safety Workgroup.

Patient safety education is a mandated Common Program Requirement of the Accreditation Council for Graduate Medical Education and for the Royal College of Physicians and Surgeons of Canada in all medical residency and fellowship programs. Although many hospitals and healthcare environments have general patient safety education tools for trainees, few to none focus on the unique training milieu of pathologists, including a mix of highly automated and manual error-prone processes, frequent multiplicity of events, and lack of direct patient relationships for error disclosure. We established a national Association of Pathology Chairs-Program Directors Section Workgroup focused on patient safety education for pathology trainees entitled Training Residents in Patient Safety (TRIPS). TRIPS included diverse representatives from across the United States, as well as representatives from pathology organizations including the American Board of Pathology, the American Society for Clinical Pathology, the United States and Canadian Academy of Pathology, the College of American Pathologists, and the Society to Improve Diagnosis in Medicine. Objectives of the workgroup included developing a standardized patient safety curriculum, designing teaching and assessment tools, and refining them with pilot sites. Here we report the establishment of TRIPS as well as data from national needs assessment of Program Directors across the country, who confirmed the need for a standardized patient safety curriculum.

Molecular genetic characterization of sudden deaths due to thoracic aortic dissection or rupture.

BACKGROUND: Sudden deaths due to thoracic aortic dissection or rupture (TADR) are often investigated by forensic pathologists in the United States. Up to a quarter of reported TADR result from a highly penetrant autosomal dominant single gene variant. Testing genes associated with familial TADR provides an underlying etiology for the cause of death and informs effective sudden death prevention for at-risk family members. At the New York City Office of Chief Medical Examiner (NYC-OCME), TADR cases are routinely tested by the in-house, CAP-accredited Molecular Genetics Laboratory. In this retrospective study, TADR and cardiovascular cases were reviewed to understand the burden of TADR in sudden deaths, value of molecular diagnostic testing in TADR, and genotype-phenotype correlations in a demographically diverse TADR cohort. METHODS: Between July 2019 and June 2022, cases with in-house cardiovascular genetic testing at NYC-OCME were retrospectively reviewed. Twenty genes associated with familial TADR were analyzed using high throughput massive parallel sequencing on postmortem tissues or bloodspot cards. Variant interpretation was conducted according to ACMG/AMP guidelines. RESULTS: A total of 1078 cases were tested for cardiovascular genetic conditions, of which 34 (3%) had TADR. Eight of those TADR cases had a pathogenic or likely pathogenic variant (P/LPV), 4 had a variant of uncertain significance (VUS), and 22 cases were negative for variants in TADR genes. The molecular diagnostic yield using the TADR subpanel was 23.5%. The genes with the greatest prevalence of P/LPV were FBN1 (6), followed by TGFBR2 (2), TGFBR1 (1), and MYLK (1). Highly penetrant P/LPV in TGFBR2, FBN1, and TGFBR1 were found in TADR individuals who died younger than 34 years old. Two P/LPV in FBN1 were secondary findings unrelated to cause of death. P/LPV in FBN1 included five truncating variants located in the N-terminal domains and one missense variant involved in the disulfide bonds of the EGF-like domain. All P/LPV in TGFBR1 and TGFBR2 were missense or in-frame deletion variants located in the protein kinase catalytic domain. Three variants were first reported in this study. CONCLUSIONS: Molecular testing of familial TADR-associated genes is a highly effective tool to identify the genetic cause of TADR sudden deaths and benefits surviving at-risk families.

Genetic screening of relatives of decedents experiencing sudden unexpected death: medical examiner's office referrals to a multi-disciplinary cardiogenetics program.

Currently, no standardized system exists for evaluating and testing at-risk family members of decedents with abnormal post-mortem genetic testing in cases of sudden unexpected death (SUD). The goal of this study was to evaluate the outcomes of referrals made by an urban medical examiner's office to a multi-disciplinary cardiogenetics clinic. Relatives of decedents with pathogenic/likely pathogenic (P/LP) variants or variants of unknown significance (VUS) in genes known to be associated with cardiomyopathies and/or arrhythmias were identified by the New York City Office of Chief Medical Examiner and referred to the Cardiogenetics Clinic at Montefiore Medical Center. Familial referrals of 15 decedents (median 15 years, range 2 days to 57 years) were evaluated. Variants in 13 genes were identified among decedents (9 arrhythmia, 5 cardiomyopathy). P/LP variants were identified in both arrhythmia (RYR2, SCN5A) and cardiomyopathy syndrome (MYBPC3 (2), MYH7) genes. Thirty-two family members were referred, and 14 variants were detected. One pathogenic (MYBPC3) and two likely pathogenic (RYR2, MYH7) mutations were identified. Referral of at-risk family members of decedents who experienced SUD based on informative post-mortem genetic testing for cardiac and genetic evaluation is warranted, as family studies help to reclassify variants and prevent additional sudden death.

Burden of Cardiomyopathic Genetic Variation in Lethal Pediatric Myocarditis.

BACKGROUND: Acute myocarditis (AM) is a well-known cause of sudden death and heart failure, often caused by prevalent viruses. We previously showed that some pediatric AM correlates with putatively damaging variants in genes related to cardiomyocyte structure and function. We sought to evaluate whether deleterious cardiomyopathic variants were enriched among fatal pediatric AM cases in New York City compared with ancestry-matched controls. METHODS: Twenty-four children (aged 3 weeks to 20 years) with death due to AM were identified through autopsy records; histologies were reviewed to confirm that all cases met Dallas criteria for AM and targeted panel sequencing of 57 cardiomyopathic genes was performed. Controls without cardiovascular disease were identified from a pediatric database and matched by genetic ancestry to cases using principal components from exome sequencing. Rates of putative deleterious variations (DV) were compared between cases and controls. Where available, AM tissues underwent viral analysis by polymerase chain reaction. RESULTS: DV were identified in 4 of 24 AM cases (16.7%), compared with 2 of 96 age and ancestry-matched controls (2.1%, P=0.014). Viral causes were proven for 6 of 8 AM cases (75%), including the one DV+ case where tissue was available for testing. DV+ cases were more likely to be female, have no evidence of chronic inflammation, and associate with sudden cardiac death than DV- cases. CONCLUSIONS: Deleterious variants in genes related to cardiomyocyte integrity are more common in children with fatal AM than controls, likely conferring susceptibility. Additionally, genetically mediated AM may progress more rapidly and be more severe.

Using postmortem formalin fixed paraffin-embedded tissues for molecular testing of sudden cardiac death: A cautionary tale of utility and limitations.

For archived cases of previously young healthy individuals where cause of sudden death remains undetermined, formalin fixed paraffin-embedded tissues (FFPE) samples are often the only biological resource available for molecular testing. We aim to ascertain the validity of postmortem molecular analysis of 95 cardiac genes using the FFPE samples routinely processed in the offices of medical examiners - typical fixation time in formalin ranges from days to months. The study was conducted in the College of American Pathologists accredited Molecular Genetics Laboratory within the City of New York Office of Chief Medical Examiner. Twelve cases, with FFPE samples and corresponding non-formalin fixed samples (RNAlater-preserved tissues or bloodstain card), were chosen for testing results comparison. The methods of extracting DNA from FFPE samples using Covaris, Qiagen, and Promega products showed comparable results. The quality of the extracted DNA, the target-enriched DNA libraries of 95 cardiac genes using HaloPlex Target Enrichment system by Agilent Technologies, and sequencing results using Illumina Miseq instrument were evaluated. Compared to the sequencing results of the nonfixed samples, the FFPE samples were categorized into three groups: 1) Group 1 samples fixed in formalin 2-6 days, had greater than 55 % sequencing regions ≥30x and 94%-100% variant concordance. 2) Group 2 samples fixed in formalin for 8 days, showed intra-sample sequencing variations: the surface tissues showed 25%-27% extra variants (false positive) and 8.1%-9.7% missing variants (false negative), whereas the repeated core tissues showed reduced extra variants to 1.6 % and the false negative error was unchanged. 3) Group 3 samples fixed in formalin 29-136 days, had 2-55 % sequencing regions ≥30x, up to 52.2 % missed variants and up to 6.3 % extra variants. All reportable variants (pathogenic, likely pathogenic or variant of uncertain significance) identified in the nonfixed samples were also identified in FFPE, albeit three variants had low confidence variant calling. In summary, our study showed that postmortem molecular diagnostic testing using FFPE samples routinely processed by the medical examiners should be cautioned, as they are replete with false positive and negative results, particularly when sample fixation time is longer than 8 days. Saving non-formalin fixed samples for high fidelity molecular analysis is strongly encouraged.

Functional characterization of SCN10A variants in several cases of sudden unexplained death.

BACKGROUND: Multiple genome-wide association studies (GWAS) and targeted gene sequencing have identified common variants in SCN10A in cases of PR and QRS duration abnormalities, atrial fibrillation and Brugada syndrome. The New York City Office of Chief Medical Examiner has now also identified five SCN10A variants of uncertain significance in six separate cases within a cohort of 330 sudden unexplained death events. The gene product of SCN10A is the Nav1.8 sodium channel. The purpose of this study was to characterize effects of these variants on Nav1.8 channel function to provide better information for the reclassification of these variants. METHODS AND RESULTS: Patch clamp studies were performed to assess effects of the variants on whole-cell Nav1.8 currents. We also performed RNA-seq analysis and immunofluorescence confocal microcopy to determine Nav1.8 expression in heart. We show that four of the five rare 'variants of unknown significance' (L388M, L867F, P1102S and V1518I) are associated with altered functional phenotypes. The R756W variant behaved similar to wild-type under our experimental conditions. We failed to detect Nav1.8 protein expression in immunofluorescence microscopy in rat heart. Furthermore, RNA-seq analysis failed to detect full-length SCN10A mRNA transcripts in human ventricle or mouse specialized cardiac conduction system, suggesting that the effect of Nav1.8 on cardiac function is likely to be extra-cardiac in origin. CONCLUSIONS: We have demonstrated that four of five SCN10A variants of uncertain significance, identified in unexplained death, have deleterious effects on channel function. These data extend the genetic testing of SUD cases, but significantly more clinical evidence is needed to satisfy the criteria needed to associate these variants with the onset of SUD.

Functional characterization of ABCC9 variants identified in sudden unexpected natural death.

BACKGROUND: Genetic variation in ion channel genes ('channelopathies') are often associated with inherited arrhythmias and sudden death. Genetic testing ('molecular autopsies') of channelopathy genes can be used to assist in determining the likely causes of sudden unexpected death. However, different in silico approaches can yield conflicting pathogenicity predictions and assessing their impact on ion channel function can assist in this regard. METHODS AND RESULTS: We performed genetic testing of cases of sudden expected death in the New York City metropolitan area and found four rare or novel variants in ABCC9, which codes for the regulatory SUR2 subunit of KATP channels. All were missense variants, causing amino acid changes in the protein. Three of the variants (A355S, M941V, and K1379Q) were in cases of infants less than six-months old and one (H1305Y) was in an adult. The predicted pathogenicities of the variants were conflicting. We have introduced these variants into a human SUR2A cDNA, which we coexpressed with the Kir6.2 pore-forming subunit in HEK-293 cells and subjected to patch clamp and biochemical assays. Each of the four variants led to gain-of-function phenotypes. The A355S and M941V variants increased in the overall patch current. The sensitivity of the KATP channels to inhibitory 'cytosolic' ATP was repressed for the M941V, H1305Y and K1379Q variants. None of the variants had any effect on the unitary KATP channel current or the surface expression of KATP channels, as determined with biotinylation assays, suggesting that all of the variants led to an enhanced open state. CONCLUSIONS: All four variants caused a gain-of-function phenotype. Given the expression of SUR2-containing KATP channels in the heart and specialized cardiac conduction, vascular smooth muscle and respiratory neurons, it is conceivable that electrical silencing of these cells may contribute to the vulnerability element, which is a component of the triple risk model of sudden explained death in infants. The gain-of-function phenotype of these ABCC9 variants should be considered when assessing their potential pathogenicity.

Genetic testing in sudden unexpected natural death in the young: New York City Office of Chief Medical Examiner's experience and perspective.

Postmortem genetic testing is a diagnostic tool that is becoming increasingly utilized. The benefits and limitations of genetic testing in cases of sudden, unexpected death in the young (≤ 40 years old) are reviewed from the perspective of the Office of Chief Medical Examiner of the City of New York, whose Molecular Genetics Laboratory, accredited by College of American Pathologists, has had 15 years of postmortem testing experience. Challenges to the interpretation and communication of testing results are highlighted, and opportunities for improving testing yield are discussed for age groups across the lifespan, from infancy to adulthood.

Functional reclassification of variants of uncertain significance in the HCN4 gene identified in sudden unexpected death.

The HCN4 gene encodes a subunit of the hyperpolarization-activated cyclic nucleotide-gated channel, type 4 that is essential for the proper generation of pacemaker potentials in the sinoatrial node. The HCN4 gene is often present in targeted genetic testing panels for various cardiac conduction system disorders and there are several reports of HCN4 variants associated with conduction disorders. Here, we report the in vitro functional characterization of four rare variants of uncertain significance (VUS) in HCN4, identified through testing a cohort of 296 sudden unexpected natural deaths. The variants are all missense alterations, leading to single amino acid changes: p.E66Q in the N-terminus, p.D546N in the C-linker domain, and both p.S935Y and p.R1044Q in the C-terminus distal to the CNBD. We also identified a likely benign variant, p. P1063T, which has a high minor allele frequency in the gnomAD, which is utilized here as a negative control. Three of the HCN4 VUS (p.E66Q, p.S935Y, and p.R1044Q) had electrophysiological characteristics similar to the wild-type channel, suggesting that these variants are benign. In contrast, the p.D546N variant in the C-linker domain exhibited a larger current density, slower activation, and was unresponsive to cyclic adenosine monophosphate (cAMP) compared to wild-type. With functional assays, we reclassified three rare HCN4 VUS to likely benign variants, eliminating the necessity for costly and time-consuming further study. Our studies also provide a new lead to investigate how a VUS located in the C-linker connecting the pore to the cAMP binding domain may affect the channel open state probability and cAMP response.

Molecular autopsy: using the discovery of a novel de novo pathogenic variant in the KCNH2 gene to inform healthcare of surviving family.

BACKGROUND: Molecular testing of the deceased (Molecular Autopsy) is an overlooked area in the United States healthcare system and is not covered by medical insurance, leading to ineffective care for surviving families of thousands of sudden unexpected natural deaths each year. We demonstrated the precision management of surviving family members through the discovery of a novel de novo pathogenic variant in a decedent. METHODS: Forensic investigation and molecular autopsy were performed on an 18-year-old female who died suddenly and unexpectedly. Co-segregation family study of the first-degree relatives and functional characterization of the variant were conducted. FINDINGS: We identified a novel nonsense variant, NP_000229.1:p.Gln1068Ter, in the long QT syndrome type II gene KCNH2 in the decedent. This finding correlated with her ante-mortem electrocardiograms. Patch clamp functional studies using transfected COS-7 cells show that hERG-ΔQ1068 has a mixed phenotype, with both gain- (negative voltage shift of steady-state activation curve, the positive shift of the steady-state inactivation curve, and accelerated activation) and loss-of function (reduced current density, reduced surface expression and accelerated deactivation) hallmarks. Loss of cumulative activation during rapid pacing demonstrates that the loss-of-function phenotype predominates. The wild-type channel did not rescue the hERG-ΔQ1068 defects, demonstrating haploinsufficiency of the heterozygous state. Targeted variant testing in the family showed that the variant in KCNH2 arose de novo, which eliminated the need for exhaustive genome testing and annual cardiac follow-up for the parents and four siblings. INTERPRETATION: Molecular testing enables accurate determination of natural causes of death and precision care of the surviving family members in a time and cost-saving manner. We advocate for molecular autopsy being included under the healthcare coverage in US.

Functional characterization of TRPM4 variants identified in sudden unexpected natural death.

BACKGROUND: The TRPM4 gene encodes the subunit of the Ca2+-activated nonselective cation channel, which is enriched in the specialized cardiac conduction system and Purkinje fibers. To date, several putative disease-causing variants in TRPM4 have been reported to be associated with cardiac arrhythmia and progressive conduction disease. Here, we report the functional effects of previously uncharacterized variants of uncertain significance (VUS) that we have found while performing a "genetic autopsy" in individuals who have suffered sudden unexpected death (SUD) in the New York City area. METHODS AND RESULTS: We have identified thirteen uncommon missense VUS in TRPM4 by testing 95 targeted genes implicated in channelopathy and cardiomyopathy in 330 cases of SUD. In several cases there were co-existing VUS in one or more other genes that were tested. We selected four TRPM4 VUS (C20S, A380V, L595V and I1082S) for functional characterization, since these cases lacked detectable variants in other genes of our testing panel. Two of the cases were infants, one was a child and one an adult. RNA-seq data analysis showed that the longer TRPM4b splice variant is predominantly expressed in adult and fetal human heart. We therefore used site-directed mutagenesis to introduce these variants in a TRPM4b cDNA. HEK293 cells were transfected with the cDNAs and patch clamping was performed to assess the functional consequences of the TRPM4 mutants. The TRPM4 current was recorded in excised patches and was significantly reduced by each of the mutants. The total protein level of TRPM4-C20S was markedly decreased, whereas the A380V and L595V mutants exhibited decreased surface expression. The TRPM4-A380V current rapidly desensitized following patch excision. CONCLUSIONS: Each of the VUS tested caused a defect in TRPM4 channel function via distinctly different mechanisms, hence, it lays the foundation for further co-segregation family studies and animal studies of the TRPM4 variants.

Phenotypic variations in carriers of predicted protein-truncating genetic variants in MYBPC3: an autopsy-based case series.

Our aim is to characterize predicted protein-truncating variants (PTVs) in MYBPC3, the gene most commonly associated with hypertrophic cardiomyopathy (HCM), found in a series of autopsied HCM cases after sudden unexpected cardiac death. All cases underwent death scene investigation, gross and microscopic autopsies, toxicological testing, a review of medical records, and a molecular analysis of 95 cardiac genes. We found four pathogenic PTVs in MYBPC3 among male decedents. All variants were previously submitted to ClinVar without phenotype details. Two PTVs were located in the cardiac-specific myosin S2-binding (M) motif at the N-terminus of the MYBPC3-encoded cMyBP-C protein, and two PTVs were in the non-cardiac-specific C-terminus of the protein. The carriers of two cardiac-specific M-motif PTVs died at age 38 years; their heart weight (HW, g) and body mass index (BMI, kg/m2) ratio were 34.90 (890/25.5) and 23.56 (980/41.6), respectively. In contrast, the carriers of two non-cardiac-specific C-terminal PTVs died at age 57 and 67 years, respectively; their HW and BMI ratio were 14.71 (450/30.6) and 13.98 (600/42.9), respectively. A detailed three-generation family study was conducted in one case. This study showed age-at-death variations among MYBPC3 PTVs carriers in adult males.

Report and Recommendations of the Association of Pathology Chairs' Autopsy Working Group.

Autopsy has been a foundation of pathology training for many years, but hospital autopsy rates are notoriously low. At the 2014 meeting of the Association of Pathology Chairs, some pathologists suggested removing autopsy from the training curriculum of pathology residents to provide additional months for training in newer disciplines, such as molecular genetics and informatics. At the same time, the American Board of Pathology received complaints that newly hired pathologists recently certified in anatomic pathology are unable to perform an autopsy when called upon to do so. In response to a call to abolish autopsy from pathology training on the one hand and for more rigorous autopsy training on the other, the Association of Pathology Chairs formed the Autopsy Working Group to examine the role of autopsy in pathology residency training. After 2 years of research and deliberation, the Autopsy Working Group recommends the following:Autopsy should remain a component of anatomic pathology training.A training program must have an autopsy service director with defined responsibilities, including accountability to the program director to record every autopsy performed by every resident.Specific entrustable activities should be defined that a resident must master in order to be deemed competent in autopsy practice, as well as criteria for gaining the trust to perform the tasks without direct supervision.Technical standardization of autopsy performance and reporting must be improved.The current minimum number of 50 autopsies should not be reduced until the changes recommended above have been implemented.

Applying High-Resolution Variant Classification to Cardiac Arrhythmogenic Gene Testing in a Demographically Diverse Cohort of Sudden Unexplained Deaths.

BACKGROUND: Genetic variant interpretation contributes to testing yield differences reported for sudden unexplained death. Adapting a high-resolution variant interpretation framework, which considers disease prevalence, reduced penetrance, genetic heterogeneity, and allelic contribution to determine the maximum tolerated allele count in gnomAD, we report an evaluation of cardiac channelopathy and cardiomyopathy genes in a large, demographically diverse sudden unexplained death cohort that underwent thorough investigation in the United States' largest medical examiner's office. METHODS AND RESULTS: The cohort has 296 decedents: 147 Blacks, 64 Hispanics, 49 Whites, 22 Asians, and 14 mixed ethnicities; 142 infants (1 to 11 months), 39 children (1 to 17 years), 74 young adults (18 to 34 years), and 41 adults (35 to 55 years). Eighty-nine cardiac disease genes were evaluated. Using a high-resolution variant interpretation workflow, we classified 17 variants as pathogenic or likely pathogenic (2 of which were incidental findings and excluded in testing yield analysis), 46 novel variants of uncertain significance, and 130 variants of uncertain significance. Nine pathogenic or likely pathogenic variants in ClinVar were reclassified to likely benign and excluded in testing yield analysis. The yields of positive cases by ethnicity and age were 21.4% in mixed ethnicities, 10.2% Whites, 4.5% Asians, 3.1% Hispanics, and 2% Blacks; 7.7% children, 7.3% in adults, 5.4% young adults, and 2.8% infants. The percentages of uncertain cases with variants of uncertain significance by ethnicity were 45.5% in Asians, 45.3% Hispanics, 44.20% Blacks, 36.7% Whites, and 14.3% in mixed ethnicities. CONCLUSIONS: High-resolution variant interpretation provides diagnostic accuracy and healthcare efficiency. Under-represented populations warrant greater inclusion in future studies.

Whole Exome Sequencing Reveals Severe Thrombophilia in Acute Unprovoked Idiopathic Fatal Pulmonary Embolism.

BACKGROUND: Acute unprovoked idiopathic fatal pulmonary embolism (IFPE) causes sudden death without an identifiable thrombogenic risk. We aimed to investigate the underlying genomic risks of IFPE through whole exome sequencing (WES). METHODS: We reviewed 14years of consecutive out-of-hospital fatal pulmonary embolism records (n=1478) from the ethnically diverse population of New York City. We selected 68 qualifying IFPE cases for WES. We compared the WES data of IFPE cases to those of 9332 controls to determine if there is an excess of rare damaging variants in the genome using ethnicity-matched controls in collapsing analyses. FINDINGS: We found nine of the 68 decedents (13·2%) who died of IFPE had at least one pathogenic or likely pathogenic variant in one of the three anti-coagulant genes: SERPINC1 (Antithrombin III), PROC, and PROS1. The odds ratio of developing IFPE as a variant carrier for SERPINC1 is 144·2 (95% CI, 26·3-779·4; P=1·7×10-7), for PROC is 85·6 (95% CI, 13·0-448·9; P=2.0×10-5), and for PROS1 is 56·4 (95% CI, 5·3-351·1; P=0·001). The average age-at-death of anti-coagulant gene variant carriers is significantly younger than that of non-carriers (28·56years versus 38·02years; P=0·01). INTERPRETATION: This study showed the important role of severe thrombophilia due to natural anti-coagulant deficiency in IFPE. Evaluating severe thrombophilia in out-of-hospital fatal PE beyond IFPE is warranted.

Trends in United States Mass Fatality Incidents and Recommendations for Medical Examiners and Coroners.

It is imperative that medicolegal jurisdictions prepare for the occurrence of a mass fatality incident. Despite the trend to plan for catastrophic and complicated incidents, this analysis of recent mass fatality events seeks to better inform authorities regarding the scale and types of incidents that could potentially impact their jurisdiction. The guidance provided by this study serves as a tool to guide the development of plans, acquisition of appropriate resources, and training of staff. To perform this analysis, data were collected from mass fatality incidents occurring in the United States from January 1, 2000 to December 31, 2016 that resulted in ten or more fatalities. Specific data points were collected for each incident including the date, location, number of fatalities, incident type (e.g., man-made or natural), incident subtype, and description (e.g., mass shooting, hurricane, aviation). A total of 137 incidents fit the criteria for inclusion in the analysis, resulting in a total of 8462 fatalities. The average number of incidents was eight per year during the study period. The analysis demonstrates that most mass fatality incidents (88.8%) result in between ten and 50 fatalities and are variable based on incident type and geographic location. This study includes several large-scale incidents, which as outliers have influenced fatality management operations and preparedness efforts on a national level. In particular, the World Trade Center attack of September 11, 2001 and subsequent remains recovery and identification operations have served to inform the New York City Office of Chief Medical Examiner of the capabilities required to manage a complex, protracted victim identification process involving extensive body fragmentation and commingling. While the World Trade Center attack has been shown to be outside the normal trends of mass fatality incidents, it has nonetheless offered the medicolegal community several invaluable lessons.