The genomic landscape of familial glioma
Choi DJ, Armstrong G, Lozzi B, Vijayaraghavan P, Plon SE, Wong TC, Boerwinkle E, Muzny DM, Chen HC, Gibbs RA, Ostrom QT, Melin B, Deneen B, Bondy ML; Gliogene Consortium; Genomics England Research Consortium; Bainbridge MN, Amos CI, Barnholtz-Sloan JS, Bernstein JL, Claus EB, Houlston RS, Il’yasova D, Jenkins RB, Johansen C, Lachance D, Lai R, Melin BS, Merrell RT, Olson SH, Sadetzki S, Schildkraut J, Shete S, Ambrose JC, Arumugam P, Bevers R, Bleda M, Boardman-Pretty F, Boustred CR, Brittain H, Brown MA, Caulfield MJ, Chan GC, Giess A, Griffin JN, Hamblin A, Henderson S, Hubbard TJP, Jackson R, Jones LJ, Kasperaviciute D, Kayikci M, Kousathanas A, Lahnstein L, Lakey A, Leigh SEA, Leong IUS, Lopez FJ, Maleady-Crowe F, McEntagart M, Minneci F, Mitchell J, Moutsianas L, Mueller M, Murugaesu N, Need AC, O’Donovan P, Odhams CA, Patch C, Perez-Gil D, Pereira MB, Pullinger J, Rahim T, Rendon A, Rogers T, Savage K, Sawant K, Scott RH, Siddiq A, Sieghart A, Smith SC, Sosinsky A, Stuckey A, Tanguy M, Taylor Tavares AL, Thomas ERA, Thompson SR, Tucci A, Welland MJ, Williams E, Witkowska K, Wood SM, Zarowiecki M.
Sci Adv. 2023 Apr 28;9(17):eade2675. doi: 10.1126/sciadv.ade2675. Epub 2023 Apr 28.
Glioma is a rare brain tumor with a poor prognosis. Familial glioma is a subset of glioma with a strong genetic predisposition that accounts for approximately 5% of glioma cases. We performed whole-genome sequencing on an exploratory cohort of 203 individuals from 189 families with a history of familial glioma and an additional validation cohort of 122 individuals from 115 families. We found significant enrichment of rare deleterious variants of seven genes in both cohorts, and the most significantly enriched gene was HERC2 (P = 0.0006). Furthermore, we identified rare noncoding variants in both cohorts that were predicted to affect transcription factor binding sites or cause cryptic splicing. Last, we selected a subset of discovered genes for validation by CRISPR knockdown screening and found that DMBT1, HP1BP3, and ZCH7B3 have profound impacts on proliferation. This study performs comprehensive surveillance of the genomic landscape of familial glioma.
April 28, 2023
3D genome mapping identifies subgroup-specific chromosome conformations and tumor-dependency genes in ependymoma
Okonechnikov K, Camgöz A, Chapman O, Wani S, Park DE, Hübner JM, Chakraborty A, Pagadala M, Bump R, Chandran S, Kraft K, Acuna-Hidalgo R, Reid D, Sikkink K, Mauermann M, Juarez EF, Jenseit A, Robinson JT, Pajtler KW, Milde T, Jäger N, Fiesel P, Morgan L, Sridhar S, Coufal NG, Levy M, Malicki D, Hobbs C, Kingsmore S, Nahas S, Snuderl M, Crawford J, Wechsler-Reya RJ, Davidson TB, Cotter J, Michaiel G, Fleischhack G, Mundlos S, Schmitt A, Carter H, Michealraj KA, Kumar SA, Taylor MD, Rich J, Buchholz F, Mesirov JP, Pfister SM, Ay F, Dixon JR, Kool M, Chavez L.
Nat Commun. 2023 Apr 21;14(1):2300. doi: 10.1038/s41467-023-38044-0.
Ependymoma is a tumor of the brain or spinal cord. The two most common and aggressive molecular groups of ependymoma are the supratentorial ZFTA-fusion associated and the posterior fossa ependymoma group A. In both groups, tumors occur mainly in young children and frequently recur after treatment. Although molecular mechanisms underlying these diseases have recently been uncovered, they remain difficult to target and innovative therapeutic approaches are urgently needed. Here, we use genome-wide chromosome conformation capture (Hi-C), complemented with CTCF and H3K27ac ChIP-seq, as well as gene expression and DNA methylation analysis in primary and relapsed ependymoma tumors, to identify chromosomal conformations and regulatory mechanisms associated with aberrant gene expression. In particular, we observe the formation of new topologically associating domains (‘neo-TADs’) caused by structural variants, group-specific 3D chromatin loops, and the replacement of CTCF insulators by DNA hyper-methylation. Through inhibition experiments, we validate that genes implicated by these 3D genome conformations are essential for the survival of patient-derived ependymoma models in a group-specific manner. Thus, this study extends our ability to reveal tumor-dependency genes by 3D genome conformations even in tumors that lack targetable genetic alterations.
April 21, 2023
Clinical and molecular spectrum of a large Egyptian cohort with ALS2-related disorders of infantile-onset of clinical continuum IAHSP/JPLS
Zaki MS, Sharaf-Eldin WE, Rafat K, Elbendary HM, Kamel M, Elkhateeb N, Noureldeen MM, Abdeltawab MA, Sadek AA, Essawi ML, Lau T, Murphy D, Abdel-Hamid MS, Holuden H, Issa MY, Gleeson JG.
Clin Genet. 2023 Apr 13. doi: 10.1111/cge.14338. Online ahead of print.
This study presents 46 patients from 23 unrelated Egyptian families with ALS2-related disorders without evidence of lower motor neuron involvement. Age at onset ranged from 10 months to 2.5 years, featuring progressive upper motor neuron signs. Detailed clinical phenotypes demonstrated inter- and intrafamilial variability. We identified 16 homozygous disease-causing ALS2 variants; sorted as splice-site, missense, frameshift, nonsense and in-frame in eight, seven, four, three, and one families, respectively. Seven of these variants were novel, expanding the mutational spectrum of the ALS2 gene. As expected, clinical severity was positively correlated with disease onset (p = 0.004). This work provides clinical and molecular profiles of a large single ethnic cohort of patients with ALS2 mutations, and suggests that infantile ascending hereditary spastic paralysis (IAHSP) and juvenile primary lateral sclerosis (JPLS) are belonged to one entity with no phenotype-genotype correlation.
April 13, 2023
Rapid Whole Genome Sequencing for Diagnosis of Single Locus Genetic Diseases in Critically Ill Children
Owen MJ, Batalov S, Ellsworth KA, Wright M, Breeding S, Hugh K, Kingsmore SF, Ding Y.
Methods Mol Biol. 2023;2621:217-239. doi: 10.1007/978-1-0716-2950-5_12.
Upon admission to intensive care units (ICU), the differential diagnosis of almost all infants with diseases of unclear etiology includes single locus genetic diseases. Rapid whole genome sequencing (rWGS), including sample preparation, short-read sequencing-by-synthesis, informatics pipelining, and semiautomated interpretation, can now identify nucleotide and structural variants associated with most genetic diseases with robust analytic and diagnostic performance in as little as 13.5 h. Early diagnosis of genetic diseases transforms medical and surgical management of infants in ICUs, minimizing both the duration of empiric treatment and the delay to start of specific treatment. Both positive and negative rWGS tests have clinical utility and can improve outcomes. Since first described 10 years ago, rWGS has evolved considerably. Here we describe our current methods for routine diagnostic testing for genetic diseases by rWGS in as little as 18 h.
April 12, 2023
RPM for NICU and PICUrWGS
Isolated Absent Aortic Valves: A Unique Fetal Case With Echocardiographic, Pathologic, and Genetic Correlation
Schuchardt EL, Grossfeld P, Kingsmore S, Ding Y, Vargas LA, Dyar DA, Mendoza A, Dummer KB.
JACC Case Rep. 2023 Feb 22;11:101790. doi: 10.1016/j.jaccas.2023.101790. eCollection 2023 Apr 5.
We present a 22-week fetus with isolated absent aortic valve and inverse circular shunt. The pregnancy was interrupted. Here, echocardiography and pathology images demonstrate this rare entity. Whole genome sequencing revealed a potentially disease-causing variant in the APC gene. Whole genome sequencing should be considered in severe and rare fetal diseases. (Level of Difficulty: Advanced.).
April 5, 2023
Automated prioritization of sick newborns for whole genome sequencing using clinical natural language processing and machine learning
Peterson B, Hernandez EJ, Hobbs C, Malone Jenkins S, Moore B, Rosales E, Zoucha S, Sanford E, Bainbridge MN, Frise E, Oriol A, Brunelli L, Kingsmore SF, Yandell M.
Genome Med. 2023 Mar 16;15(1):18. doi: 10.1186/s13073-023-01166-7.
BACKGROUND: Rapidly and efficiently identifying critically ill infants for whole genome sequencing (WGS) is a costly and challenging task currently performed by scarce, highly trained experts and is a major bottleneck for application of WGS in the NICU. There is a dire need for automated means to prioritize patients for WGS.
METHODS: Institutional databases of electronic health records (EHRs) are logical starting points for identifying patients with undiagnosed Mendelian diseases. We have developed automated means to prioritize patients for rapid and whole genome sequencing (rWGS and WGS) directly from clinical notes. Our approach combines a clinical natural language processing (CNLP) workflow with a machine learning-based prioritization tool named Mendelian Phenotype Search Engine (MPSE).
RESULTS: MPSE accurately and robustly identified NICU patients selected for WGS by clinical experts from Rady Children’s Hospital in San Diego (AUC 0.86) and the University of Utah (AUC 0.85). In addition to effectively identifying patients for WGS, MPSE scores also strongly prioritize diagnostic cases over non-diagnostic cases, with projected diagnostic yields exceeding 50% throughout the first and second quartiles of score-ranked patients.
CONCLUSIONS: Our results indicate that an automated pipeline for selecting acutely ill infants in neonatal intensive care units (NICU) for WGS can meet or exceed diagnostic yields obtained through current selection procedures, which require time-consuming manual review of clinical notes and histories by specialized personnel.
March 16, 2023
RPM for NICU and PICUrWGS
Genomic sequencing has a high diagnostic yield in children with congenital anomalies of the heart and urinary system
Allred ET, Perens EA, Coufal NG, Sanford Kobayashi E, Kingsmore SF, Dimmock DP.
Front Pediatr. 2023 Mar 14;11:1157630. doi: 10.3389/fped.2023.1157630. eCollection 2023.
BACKGROUND: Congenital heart defects (CHD) and congenital anomalies of the kidney and urinary tract (CAKUT) account for significant morbidity and mortality in childhood. Dozens of monogenic causes of anomalies in each organ system have been identified. However, even though 30% of CHD patients also have a CAKUT and both organs arise from the lateral mesoderm, there is sparse overlap of the genes implicated in the congenital anomalies for these organ systems. We sought to determine whether patients with both CAKUT and CHD have a monogenic etiology, with the long-term goal of guiding future diagnostic work up and improving outcomes.
METHODS: Retrospective review of electronic medical records (EMR), identifying patients admitted to Rady Children’s Hospital between January 2015 and July 2020 with both CAKUT and CHD who underwent either whole exome sequencing (WES) or whole genome sequencing (WGS). Data collected included demographics, presenting phenotype, genetic results, and mother’s pregnancy history. WGS data was reanalyzed with a specific focus on the CAKUT and CHD phenotype. Genetic results were reviewed to identify causative, candidate, and novel genes for the CAKUT and CHD phenotype. Associated additional structural malformations were identified and categorized.
RESULTS: Thirty-two patients were identified. Eight patients had causative variants for the CAKUT/CHD phenotype, three patients had candidate variants, and three patients had potential novel variants. Five patients had variants in genes not associated with the CAKUT/CHD phenotype, and 13 patients had no variant identified. Of these, eight patients were identified as having possible alternative causes for their CHD/CAKUT phenotype. Eighty-eight percent of all CAKUT/CHD patients had at least one additional organ system with a structural malformation.
CONCLUSIONS: Overall, our study demonstrated a high rate of monogenic etiologies in hospitalized patients with both CHD and CAKUT, with a diagnostic rate of 44%. Thus, physicians should have a high suspicion for genetic disease in this population. Together, these data provide valuable information on how to approach acutely ill patients with CAKUT and CHD, including guiding diagnostic work up for associated phenotypes, as well as novel insights into the genetics of CAKUT and CHD overlap syndromes in hospitalized children.
March 14, 2023
RPM for NICU and PICU
Scalable, high quality, whole genome sequencing from archived, newborn, dried blood spots
Ding Y, Owen M, Le J, Batalov S, Chau K, Kwon YH, Van Der Kraan L, Bezares-Orin Z, Zhu Z, Veeraraghavan N, Nahas S, Bainbridge M, Gleeson J, Baer RJ, Bandoli G, Chambers C, Kingsmore SF.
NPJ Genom Med. 2023 Feb 14;8(1):5. doi: 10.1038/s41525-023-00349-w.
Universal newborn screening (NBS) is a highly successful public health intervention. Archived dried bloodspots (DBS) collected for NBS represent a rich resource for population genomic studies. To fully harness this resource in such studies, DBS must yield high-quality genomic DNA (gDNA) for whole genome sequencing (WGS). In this pilot study, we hypothesized that gDNA of sufficient quality and quantity for WGS could be extracted from archived DBS up to 20 years old without PCR (Polymerase Chain Reaction) amplification. We describe simple methods for gDNA extraction and WGS library preparation from several types of DBS. We tested these methods in DBS from 25 individuals who had previously undergone diagnostic, clinical WGS and 29 randomly selected DBS cards collected for NBS from the California State Biobank. While gDNA from DBS had significantly less yield than from EDTA blood from the same individuals, it was of sufficient quality and quantity for WGS without PCR. All samples DBS yielded WGS that met quality control metrics for high-confidence variant calling. Twenty-eight variants of various types that had been reported clinically in 19 samples were recapitulated in WGS from DBS. There were no significant effects of age or paper type on WGS quality. Archived DBS appear to be a suitable sample type for WGS in population genomic studies.
February 14, 2023
Newborn ScreeningRPM for NICU and PICUrWGS
Reclassification of the Etiology of Infant Mortality With Whole-Genome Sequencing
Owen MJ, Wright MS, Batalov S, Kwon Y, Ding Y, Chau KK, Chowdhury S, Sweeney NM, Kiernan E, Richardson A, Batton E, Baer RJ, Bandoli G, Gleeson JG, Bainbridge M, Chambers CD, Kingsmore SF.
JAMA Netw Open. 2023 Feb 1;6(2):e2254069. doi: 10.1001/jamanetworkopen.2022.54069.
IMPORTANCE: Understanding the causes of infant mortality shapes public health, surveillance, and research investments. However, the association of single-locus (mendelian) genetic diseases with infant mortality is poorly understood.
OBJECTIVE: To determine the association of genetic diseases with infant mortality.
DESIGN, SETTING, AND PARTICIPANTS: This cohort study was conducted at a large pediatric hospital system in San Diego County (California) and included 546 infants (112 infant deaths [20.5%] and 434 infants [79.5%] with acute illness who survived; age, 0 to 1 year) who underwent diagnostic whole-genome sequencing (WGS) between January 2015 and December 2020. Data analysis was conducted between 2015 and 2022.
EXPOSURE: Infants underwent WGS either premortem or postmortem with semiautomated phenotyping and diagnostic interpretation.
MAIN OUTCOMES AND MEASURES: Proportion of infant deaths associated with single-locus genetic diseases.
RESULTS: Among 112 infant deaths (54 girls [48.2%]; 8 [7.1%] African American or Black, 1 [0.9%] American Indian or Alaska Native, 8 [7.1%] Asian, 48 [42.9%] Hispanic, 1 [0.9%] Native Hawaiian or Pacific Islander, and 34 [30.4%] White infants) in San Diego County between 2015 and 2020, single-locus genetic diseases were the most common identifiable cause of infant mortality, with 47 genetic diseases identified in 46 infants (41%). Thirty-nine (83%) of these diseases had been previously reported to be associated with childhood mortality. Twenty-eight death certificates (62%) for 45 of the 46 infants did not mention a genetic etiology. Treatments that can improve outcomes were available for 14 (30%) of the genetic diseases. In 5 of 7 infants in whom genetic diseases were identified postmortem, death might have been avoided had rapid, diagnostic WGS been performed at time of symptom onset or regional intensive care unit admission.
CONCLUSIONS AND RELEVANCE: In this cohort study of 112 infant deaths, the association of genetic diseases with infant mortality was higher than previously recognized. Strategies to increase neonatal diagnosis of genetic diseases and immediately implement treatment may decrease infant mortality. Additional study is required to explore the generalizability of these findings and measure reduction in infant mortality.
February 9, 2023