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Genetic disorders are a leading contributor to mortality in neonatal and pediatric intensive care units (ICUs). Rapid whole-genome sequencing (rWGS)-based rapid precision medicine (RPM) is an intervention that has demonstrated improved clinical outcomes and reduced costs of care. However, the feasibility of broad clinical deployment has not been established. The objective of this study was to implement RPM based on rWGS and evaluate the clinical and economic impact of this implementation as a first line diagnostic test in the California Medicaid (Medi-Cal) program. Project Baby Bear was a payor funded, prospective, real-world quality improvement project in the regional ICUs of five tertiary care children's hospitals. Participation was limited to acutely ill Medi-Cal beneficiaries who were admitted November 2018 to May 2020, were

PURPOSE Missense variants clustering in the BTB domain region of RHOBTB2 cause a developmental and epileptic encephalopathy (DEE) with early-onset seizures and severe intellectual disability. METHODS By international collaboration we assembled individuals with pathogenic RHOBTB2 variants and a variable spectrum of neurodevelopmental disorders (NDDs). By western blotting we investigated the consequences of missense variants in vitro. RESULTS In accordance with previous observations, de novo heterozygous missense variants in the BTB domain region led to a severe DEE in 16 individuals. We now identified also de novo missense variants in the GTPase domain in six individuals with apparently more variable neurodevelopmental phenotypes with or without epilepsy. In contrast to variants in the BTB domain region, variants in the GTPase domain do not impair proteasomal degradation of RHOBTB2 in vitro, indicating different functional consequences.Furthermore, we observed bi-allelic splice-site and truncating variants in nine families with variable neurodevelopmental phenotypes, indicating that complete loss of RHOBTB2 is pathogenic as well. CONCLUSION By identifying phenotype-genotype correlations regarding location and consequences of de novo missense variants in RHOBTB2 and by identifying bi-allelic truncating variants, we further delineate and expand the molecular and clinical spectrum of RHOBTB2 related disorders including both autosomal dominant and recessive NDDs.

Introduction - The COVID 19 pandemic led to restrictions on the conventional ways of healthcare delivery. Telemedicine provided a viable solution that was in line with the social distancing policies imposed to minimize disease transmission. This demanded physicians adapt to new ways of healthcare delivery. We surveyed geneticists across the country to determine their experience and to ascertain if telegenetics will be a lasting change. Materials and Methods - A 23 item standardized survey was distributed to various US-based geneticists via email and other social media platforms focusing on their experience of providing care via telemedicine. Results - We received 69 responses from physicians across 26 states. Of these, 91% practiced in academia. 70% responded that pediatric genetics takes up more than 50% of their practice. 68% had over 50% of their practice switch to telemedicine. 77% felt they could provide adequate care via telemedicine and 94% of providers would like to continue telemedicine post-pandemic. Conclusion - The future of telemedicine looks promising as the majority of clinicians would like to routinely use telemedicine post-pandemic. Uniform guidelines for use of telemedicine in genetics may need to be proposed by professional societies and supported by federal laws.

We report 281 individuals carrying a pathogenic recurrent NF1 missense variant at p.Met1149, p.Arg1276, or p.Lys1423, representing three nontruncating NF1 hotspots in the University of Alabama at Birmingham (UAB) cohort, together identified in 1.8% of unrelated NF1 individuals. About 25% (95% confidence interval: 20.5-31.2%) of individuals heterozygous for a pathogenic NF1 p.Met1149, p.Arg1276, or p.Lys1423 missense variant had a Noonan-like phenotype, which is significantly more compared with the "classic" NF1-affected cohorts (all p < .0001). Furthermore, p.Arg1276 and p.Lys1423 pathogenic missense variants were associated with a high prevalence of cardiovascular abnormalities, including pulmonic stenosis (all p < .0001), while p.Arg1276 variants had a high prevalence of symptomatic spinal neurofibromas (p < .0001) compared with "classic" NF1-affected cohorts. However, p.Met1149-positive individuals had a mild phenotype, characterized mainly by pigmentary manifestations without externally visible plexiform neurofibromas, symptomatic spinal neurofibromas or symptomatic optic pathway gliomas. As up to 0.4% of unrelated individuals in the UAB cohort carries a p.Met1149 missense variant, this finding will contribute to more accurate stratification of a significant number of NF1 individuals. Although clinically relevant genotype-phenotype correlations are rare in NF1, each affecting only a small percentage of individuals, together they impact counseling and management of a significant number of the NF1 population.

Background Biallelic variants in PIGW have been suggested to cause infantile spasms and hyperphosphatasia. PIGW encodes for a protein involved in the third step of glycosylphosphatidylinositol (GPI) synthesis. GPI anchored proteins are increasingly recognized as important structures for cellular interactions and neuronal development. Methods Molecular testing of PIGW was performed followed by fluorescence activating cell sorting analysis of granulocytes, lymphocytes, and monocytes, and compared to controls. Findings An infant was homozygous for variants in PIGW (c.199C>G; p.Pro67Ala) with an associated phenotype of infantile spasms, myoclonic seizures, cortical visual impairment, developmental delay, and minor dysmorphic features. Alkaline phosphatase levels ranged from normal to mildly elevated. Flow cytometric studies showed significantly decreased expression of important GPIs, providing functional evidence of pathogenicity. Conclusion Our data provide further evidence of a novel autosomal recessive PIGW-related epilepsy disorder. Flow cytometry provided functional evidence of the pathogenicity of homozygous variants of uncertain significance in PIGW, and supports the use of flow cytometry as a functional tool to demonstrate decreased surface expression of GPI anchored proteins in individuals with variants of unknown significance.

Neurofibromatosis type 1 (NF1), one of the most common genetic disorders with an estimated prevalence of 1:3000 live births, is characterized by a highly variable clinical presentation. To date, only two clinically relevant intragenic genotype-phenotype correlations have been reported for NF1 missense mutations affecting p.Arg1809 and an in-frame 1-amino acid deletion p.Met922del. Both variants predispose to a distinct mild NF1 phenotype with neither externally visible cutaneous/plexiform neurofibromas nor other tumors. Here, we report 162 patients (129 unrelated probands and 33 affected relatives) carrying a constitutional missense mutation affecting one of five neighboring NF1 codons Leu844, Cys845, Ala846, Leu847 and Gly848, located in the Cysteine-Serine-Rich Domain (CSRD). These recurrent missense mutations affect ~0.8% of unrelated NF1 mutation-positive probands in the UAB cohort. A substantial fraction of these patients presented with a severe phenotype, including plexiform and/or spinal neurofibromas, symptomatic optic pathway gliomas, malignant neoplasms or osseous lesions. Major superficial plexiform neurofibromas and symptomatic spinal neurofibromas were more prevalent compared with classic NF1 cohorts (both p

Background: Infantile myofibromatosis is a rare disease characterized by solitary or multiple benign tumors. Aggressive myofibromatosis with extensive visceral involvement at birth is a very rare condition with poor prognosis. Case report: We report a term male infant born with multi-system myofibromatosis involving the skin, bone, brain, heart, lung, and GI tract. The patient received chemotherapy but had a protracted clinical course complicated by intestinal obstruction and perforation, and failure to thrive. Pathology of the tumor showed presence of spindle cells. Immunohistochemical analysis of this tissue was positive for vimentin, smooth muscle actin, and CD34 but negative for Muscle-Specific Actin (MSA) and desmin. Also, electron microscopic analysis detected the presence of subcellular myofibroblastic structures. Next generation sequencing analysis of the patient’s blood and tumor tissues identified a germline mutation in PDGFRB gene p. R561C allele (c.1681C>T), as well as a second activating PDGFRB mutation (p. N666S) which was present in the tumor tissue only. Parental testing showed that the germline mutation was inherited from the father, who was asymptomatic. The second mutation is likely responsible for the aggressive nature of the condition in this patient. He eventually died due to cardiorespiratory failure. Conclusion: Early diagnosis by pathology and genetic analysis in patients’ with extensive myofibromatosis will help to determine targeted chemotherapy and prognosis.

The acromelic dysplasias comprise short stature, hands and feet, and stiff joints. Three disorders are ascribed to this group, namely Weill-Marchesani syndrome, geleophysic dysplasia, and acromicric dysplasia, although similar in phenotype, can be distinguished clinically. Weill-Marchesani syndrome, on the basis of microspherophakia and ectopia lentis; geleophysic dysplasia by progressive cardiac valvular thickening, tracheal stenosis, and/or bronchopulmonary insufficiency, often leading to early death. Microspherophakia has not been reported previously in geleophysic dysplasia. Mutations in FBN1, ADAMTS10, or ADAMTS17 cause Weill-Marchesani syndrome by disrupting the microfibrillar environment, while geleophysic dysplasia is associated with enhanced TGF-β signaling mediated through mutations in FBN1 or ADAMTSL2. We studied a 35-year-old woman with geleophysic dysplasia, with short stature, small hands and feet, limitation of joint mobility, mild skin thickening, cardiac valvular disease, restrictive pulmonary disease, and microspherophakia. Sequencing of ADAMTSL2 demonstrated two changes: IVS8-2A>G consistent with a disease-causing mutation, and IVS14-7G>A with potential to generate a new splice acceptor site and result in aberrant mRNA processing. The unaffected mother carries only the IVS8-2A>G transition providing evidence that the two changes are in trans-configuration in our patient.