The case for early use of rapid whole-genome sequencing in management of critically ill infants: late diagnosis of Coffin-Siris syndrome in an infant with left congenital diaphragmatic hernia, congenital heart disease, and recurrent infections.

Congenital diaphragmatic hernia (CDH) results from incomplete formation of the diaphragm leading to herniation of abdominal organs into the thoracic cavity. CDH is associated with pulmonary hypoplasia, congenital heart disease, and pulmonary hypertension. Genetically, it is associated with aneuploidies, chromosomal copy-number variants, and single gene mutations. CDH is the most expensive noncardiac congenital defect. Management frequently requires implementation of extracorporeal membrane oxygenation (ECMO), which increases management expenditures 2.4-3.5-fold. The cost of management of CDH has been estimated to exceed $250 million per year. Despite in-hospital survival of 80%-90%, current management is imperfect, as a great proportion of surviving children have long-term functional deficits. We report the case of a premature infant prenatally diagnosed with CDH and congenital heart disease, who had a protracted and complicated course in the intensive care unit with multiple surgical interventions, including postcardiac surgery ECMO, gastrostomy tube placement with Nissen fundoplication, tracheostomy for respiratory failure, recurrent infections, and developmental delay. Rapid whole-genome sequencing (rWGS) identified a de novo, likely pathogenic, c.3096_ 3100delCAAAG (p.Lys1033Argfs*32) variant in ARID1B, providing a diagnosis of Coffin-Siris syndrome. Her parents elected palliative care and she died later that day

Retrospective identification of prenatal fetal anomalies associated with diagnostic neonatal genomic sequencing results.

ObjectiveTo determine which types of fetal anomalies are associated with postnatal diagnoses of genetic diseases by genomic sequencing and to assess how prenatal genomic sequencing could affect clinical management.MethodThis was a secondary analysis of the second Newborn Sequencing in Genomic Medicine and Public Health study that compared fetal imaging results in critically ill infants who had actionable versus negative postnatal genomic sequencing results.ResultsOf 213 infants who received genomic sequencing, 80 had available prenatal ultrasounds. Twenty-one (26%) of these were found to have genetic diseases by genomic sequencing. Fourteen (67%) of the 21 with genetic diseases had suspected anomalies prenatally, compared with 33 (56%) of 59 with negative results. Among fetuses with suspected anomalies, genetic diseases were 4.5 times more common in those with multiple anomalies and 6.7 times more common in those with anomalies of the extremities compared to those with negative results. Had the genetic diseases been diagnosed prenatally, clinical management would have been altered in 13 of 14.ConclusionCritically ill infants with diagnostic genomic sequencing were more likely to have multiple anomalies and anomalies of the extremities on fetal imaging. Among almost all infants with suspected fetal anomalies and diagnostic genomic sequencing results, prenatal diagnosis would have likely altered clinical management

Amphetamines promote mitochondrial dysfunction and DNA damage in pulmonary hypertension

Amphetamine (AMPH) or methamphetamine (METH) abuse can cause oxidative damage and is a risk factor for diseases including pulmonary arterial hypertension (PAH). Pulmonary artery endothelial cells (PAECs) from AMPH-associated-PAH patients show DNA damage as judged by γH2AX foci and DNA comet tails. We therefore hypothesized that AMPH induces DNA damage and vascular pathology by interfering with normal adaptation to an environmental perturbation causing oxidative stress. Consistent with this, we found that AMPH alone does not cause DNA damage in normoxic PAECs, but greatly amplifies DNA damage in hypoxic PAECs. The mechanism involves AMPH activation of protein phosphatase 2A, which potentiates inhibition of Akt. This increases sirtuin 1, causing deacetylation and degradation of HIF1α, thereby impairing its transcriptional activity, resulting in a reduction in pyruvate dehydrogenase kinase 1 and impaired cytochrome c oxidase 4 isoform switch. Mitochondrial oxidative phosphorylation is inappropriately enhanced and, as a result of impaired electron transport and mitochondrial ROS increase, caspase-3 is activated and DNA damage is induced. In mice given binge doses of METH followed by hypoxia, HIF1α is suppressed and pulmonary artery DNA damage foci are associated with worse pulmonary vascular remodeling. Thus, chronic AMPH/METH can induce DNA damage associated with vascular disease by subverting the adaptive responses to oxidative stress

Reclassification of the Etiology of Infant Mortality With Whole-Genome Sequencing.

ImportanceUnderstanding 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.ObjectiveTo determine the association of genetic diseases with infant mortality.Design, setting, and participantsThis 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.ExposureInfants underwent WGS either premortem or postmortem with semiautomated phenotyping and diagnostic interpretation.Main outcomes and measuresProportion of infant deaths associated with single-locus genetic diseases.ResultsAmong 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 relevanceIn 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

Rapid Whole Genome Sequencing Has Clinical Utility in Children in the PICU.

OBJECTIVES:Genetic disorders are a leading contributor to mortality in the neonatal ICU and PICU in the United States. Although individually rare, there are over 6,200 single-gene diseases, which may preclude a genetic diagnosis prior to ICU admission. Rapid whole genome sequencing is an emerging method of diagnosing genetic conditions in time to affect ICU management of neonates; however, its clinical utility has yet to be adequately demonstrated in critically ill children. This study evaluates next-generation sequencing in pediatric critical care. DESIGN:Retrospective cohort study. SETTING:Single-center PICU in a tertiary children's hospital. PATIENTS:Children 4 months to 18 years admitted to the PICU who were nominated between July 2016 and May 2018. INTERVENTIONS:Rapid whole genome sequencing with targeted phenotype-driven analysis was performed on patients and their parents, when parental samples were available. MEASUREMENTS AND MAIN RESULTS:A molecular diagnosis was made by rapid whole genome sequencing in 17 of 38 children (45%). In four of the 17 patients (24%), the genetic diagnoses led to a change in management while in the PICU, including genome-informed changes in pharmacotherapy and transition to palliative care. Nine of the 17 diagnosed children (53%) had no dysmorphic features or developmental delay. Eighty-two percent of diagnoses affected the clinical management of the patient and/or family after PICU discharge, including avoidance of biopsy, administration of factor replacement, and surveillance for disorder-related sequelae. CONCLUSIONS:This study demonstrates a retrospective evaluation for undiagnosed genetic disease in the PICU and clinical utility of rapid whole genome sequencing in a portion of critically ill children. Further studies are needed to identify PICU patients who will benefit from rapid whole genome sequencing early in PICU admission when the underlying etiology is unclear

The fungal collaboration gradient dominates the root economics space in plants

International audiencePlant economics run on carbon and nutrients instead of money. Leaf strategies aboveground span an economic spectrum from "live fast and die young" to "slow and steady," but the economy defined by root strategies below-ground remains unclear. Here, we take a holistic view of the belowground economy and show that root-mycorrhizal collaboration can short circuit a one-dimensional economic spectrum, providing an entire space of economic possibilities. Root trait data from 1810 species across the globe confirm a classical fast-slow "conservation" gradient but show that most variation is explained by an orthogonal "collaboration" gradient, ranging from "do-it-yourself" resource uptake to "outsourcing" of resource uptake to mycorrhizal fungi. This broadened "root economics space" provides a solid foundation for predictive understanding of belowground responses to changing environmental conditions

PPARγ Interaction with UBR5/ATMIN Promotes DNA Repair to Maintain Endothelial Homeostasis

Summary: Using proteomic approaches, we uncovered a DNA damage response (DDR) function for peroxisome proliferator activated receptor γ (PPARγ) through its interaction with the DNA damage sensor MRE11-RAD50-NBS1 (MRN) and the E3 ubiquitin ligase UBR5. We show that PPARγ promotes ATM signaling and is essential for UBR5 activity targeting ATM interactor (ATMIN). PPARγ depletion increases ATMIN protein independent of transcription and suppresses DDR-induced ATM signaling. Blocking ATMIN in this context restores ATM activation and DNA repair. We illustrate the physiological relevance of PPARγ DDR functions by using pulmonary arterial hypertension (PAH) as a model that has impaired PPARγ signaling related to endothelial cell (EC) dysfunction and unresolved DNA damage. In pulmonary arterial ECs (PAECs) from PAH patients, we observed disrupted PPARγ-UBR5 interaction, heightened ATMIN expression, and DNA lesions. Blocking ATMIN in PAH PAEC restores ATM activation. Thus, impaired PPARγ DDR functions may explain the genomic instability and loss of endothelial homeostasis in PAH. : Li et al. identify PPARγ interactions with MRN and UBR5. PPARγ promotes UBR5-mediated ATMIN degradation, necessary for ATM activation upon DNA damage. Pulmonary arterial hypertension (PAH) endothelial cells exhibit genomic instability and disrupted PPARγ-UBR5 interaction. Blocking ATMIN restores ATM signaling in these cells, highlighting the significance of the PPARγ-ATMIN axis. Keywords: PPARγ, DNA damage, vascular biology, pulmonary hypertension, endothelial cells, ATM, MR