Detecting, Quantifying, and Discriminating the Mechanism of Mosaic Chromosomal Aneuploidies Using MAD-seq

Current approaches to detect and characterize mosaic chromosomal aneuploidy are limited by sensitivity, efficiency, cost, or the need to culture cells. We describe the mosaic aneuploidy detection by massively parallel sequencing (MAD-seq) capture assay and the MADSEQ analytical approach that allow low

221 Newborn-Screened Neonates with Medium-Chain Acyl-Coenzyme A Dehydrogenase Deficiency: Findings from the Inborn Errors of Metabolism Collaborative

Introduction: There is limited understanding of relationships between genotype, phenotype and other conditions contributing to health in neonates with medium-chain acyl-coenzyme A dehydrogenase deficiency (MCADD) identified through newborn screening. Methods: Retrospective analysis of comprehensive data from a cohort of 221 newborn-screened subjects identified as affected with MCADD in the Inborn Errors of Metabolism-Information System (IBEM-IS), a long term follow-up database of the Inborn Errors of Metabolism Collaborative, was performed. Results: The average age at notification of first newborn screen results to primary care or metabolic providers was 7.45 days. The average octanoylcamitine (C8) value on first newborn screen was 11.2 mu mol/L (median 8.6, range 036-43.91). A higher C8 level correlated with an earlier first subspecialty visit. Subjects with low birth weight had significantly lower C8 values. Significantly higher C8 values were found in symptomatic newborns, in newborns with abnormal lab testing in addition to newborn screening and/or diagnostic tests, and in subjects homozygous for the c.985A\u3eG ACADM gene mutation or compound heterozygous for the c.985A\u3eG mutation and deletions or other known highly deleterious mutations. Subjects with neonatal symptoms, or neonatal abnormal labs, or neonatal triggers were more likely to have at least one copy of the severe c.985A\u3eG ACADM gene mutation. C8 and genotype category were significant predictors of the likelihood of having neonatal symptoms. Neonates with select triggers were more likely to have symptoms and laboratory abnormalities. Conclusions: This collaborative study is the first in the United States to describe health associations of a large cohort of newborn-screened neonates identified as affected with MCADD. The IBEM-IS has utility as a platform to better understand the characteristics of individuals with newborn-screened conditions and their follow-up interactions with the health system. (C) 2016 Elsevier Inc. All rights reserved

Sustained Immune Tolerance Induction in Enzyme Replacement Therapy-Treated CRIM-Negative Patients with Infantile Pompe Disease

BACKGROUND: Cross-reactive immunological material-negative (CRIM-negative) infantile Pompe disease (IPD) patients develop an immune response against enzyme replacement therapy (ERT) with alglucosidase alfa that nullifies ERT efficacy. Prophylactic immune tolerance induction (ITI) with rituximab, methotrexate, and IVIG successfully prevents development of deleterious rhGAA IgG antibodies; however, safety, likelihood of success, and long-term efficacy of ITI in a larger cohort remain unknown. METHODS: Clinical data were analyzed for 19 CRIM-negative IPD patients who received ITI with rituximab, methotrexate, and IVIG in the ERT-naive setting (ERT+ITI) and compared to a historical cohort of 10 CRIM-negative IPD patients on ERT monotherapy. RESULTS: ITI was safely tolerated, although infections were reported in 4 patients. Fourteen (74%) ERT+ITI patients were alive, with a median age of 44.2 months at their final assessment. The eldest survivor was 103.9 months old, with 100.2 months of follow-up after initiation of ERT+ITI. Death (n = 5) occurred at a median age of 29.2 months and was unrelated to the administration of ITI. Fifteen patients either did not seroconvert (n = 8) or maintained low titers (n = 7; defined as titers of /=51,200 at or beyond 6 months on ERT). Left ventricular mass index (LVMI) decreased from a median of 248.5 g/m2 at baseline to 76.8 g/m2 at a median time from ERT+ITI initiation to 59 weeks. ERT+ITI significantly improved overall survival (P = 0.001), eliminated/reduced antibodies at values o

Navigating Newborn Screening in the NICU: A User\u27s Guide

Newborn screening (NBS) is the largest public health program in the United States, affecting every newborn. The purpose of newborn screening is to identify newborns at risk for selected disorders during the presymptomatic phase, with the hope that early intervention can prevent disease progression. NBS began in the early 1960s following the pioneering work of Robert Guthrie with phenylketonuria. Since then, NBS has expanded, with testing available for more than 50 disorders in most states. Screening tests need to be highly automated, with high sensitivity and specificity to avoid missing patients with disease, and ensuring manageable false-positive rates. Current initiatives in NBS include timeliness to ensure that results of the screen are available by 5 days after birth for a core set of critical conditions. This has resulted in the current recommendation for NBS specimens to be collected at 24 to 48 hours after birth. False-positive rates are higher in the NICU, because of the metabolic instability of sick neonates and the immaturity of premature enzyme systems. The recommended uniform screen panel (RUSP) contains the current list of disorders screened for by most states. Additional disorders continue to be added to the RUSP as medical progress allows previously untreatable disorders to be managed successfully, and thus the need to screen emerges. The costs associated with NBS continue to climb, because despite state-mandated screening, the diagnostic evaluation and treatment of these conditions has no such mandate. This is a particular concern for disorders with annual treatment costs of several hundred thousand dollars

Hereditary Folate Malabsorption

Hereditary folate malabsorption (HFM) is characterized by folate deficiency with impaired intestinal folate absorption and impaired folate transport into the central nervous system. Findings include poor feeding, failure to thrive, and anemia. There can be leukopenia and thrombocytopenia, diarrhea and/or oral mucositis, hypoimmunoglobulinemia, and other immunologic dysfunction resulting in infections, most often Pneumocystis jerovicii pneumonia. Neurologic manifestations include developmental delays, cognitive and motor impairment, behavioral disorders and, frequently, seizures. The diagnosis of HFM is established in a proband: with anemia, impaired absorption of an oral folate load, and low cerebrospinal fluid (CSF) folate concentration (even after correction of the serum folate concentration); and/or by the identification of biallelic pathogenic variants in SLC46A1 on molecular genetic testing. Treatment of manifestations: Parenteral (intramuscular) or high-dose oral 5-formyltetrahydrofolate (5-formylTHF, folinic acid, Leucovorin(R)) or the active isomer of 5-formylTHF (Isovorin(R) or Fusilev(R)) can obviate the signs and symptoms of HFM. Dosing is aimed at achieving CSF folate trough concentrations as close as possible to the normal range for the age of the affected individual (infants and children have higher CSF folate levels than adults). Prevention of primary manifestations: Early treatment readily corrects the systemic folate deficiency and can achieve sufficient CSF folate levels to prevent the neurologic consequences of HFM. Prevention of secondary complications: In affected individuals with selective IgA deficiency, appropriate precautions for blood product transfusion should be taken. Surveillance: To assess adequacy of treatment, surveillance should include: periodic complete blood counts; measurements of serum and CSF folate concentrations; measurements of serum and CSF homocysteine concentrations; and monitoring of the affected individual\u27s neurologic status. Serial measurement of immunoglobulins is not necessary once the levels return to the normal range and serum folate and hemoglobin levels remain normal and stable. Agents/circumstances to avoid: If possible, folic acid should not be used for the treatment of HFM because it binds very tightly to the folate receptor. This may impair transport of physiologic folates across the choroid plexus. Evaluation of relatives at risk: For at-risk sibs, molecular genetic testing when the family-specific pathogenic variants are known; otherwise, assessment of blood and CSF folate levels and, if warranted, intestinal absorption of folate immediately after birth, or as soon as the diagnosis is confirmed in the proband. Pregnancy management: Affected women should increase their folate intake above the maintenance dose prior to attempting to conceive; infants with HFM do not appear to be at an increased risk for neural malformations typically associated with maternal folate deficiency during pregnancy. HFM is inherited in an autosomal recessive manner. Heterozygotes (carriers) are asymptomatic and do not have clinical signs of folate deficiency. At conception, each sib of an affected individual has a 25% chance of being affected, a 50% chance of being an asymptomatic carrier, and a 25% chance of being unaffected and not a carrier. If both pathogenic variants have been identified in the family, carrier testing for at-risk relatives, prenatal diagnosis for a pregnancy at increased risk, and preimplantation genetic diagnosis for HFM are possible

Variants in the Degron of AFF3 are Associated with Intellectual Disability, Mesomelic Dsplasia, Horseshoe Kidney, and Epileptic Encephalopathy

The ALF transcription factor paralogs, AFF1, AFF2, AFF3, and AFF4, are components of the transcriptional super elongation complex that regulates expression of genes involved in neurogenesis and development. We describe an autosomal dominant disorder associated with de novo missense variants in the degron of AFF3, a nine amino acid sequence important for its binding to ubiquitin ligase, or with de novo deletions of this region. The sixteen affected individuals we identified, along with two previously reported individuals, present with a recognizable pattern of anomalies, which we named KINSSHIP syndrome (KI for horseshoe kidney, NS for Nievergelt/Savarirayan type of mesomelic dysplasia, S for seizures, H for hypertrichosis, I for intellectual disability, and P for pulmonary involvement), partially overlapping the AFF4-associated CHOPS syndrome. Whereas homozygous Aff3 knockout mice display skeletal anomalies, kidney defects, brain malformations, and neurological anomalies, knockin animals modeling one of the microdeletions and the most common of the missense variants identified in affected individuals presented with lower mesomelic limb deformities like KINSSHIP-affected individuals and early lethality, respectively. Overexpression of AFF3 in zebrafish resulted in body axis anomalies, providing some support for the pathological effect of increased amount of AFF3. The only partial phenotypic overlap of AFF3- and AFF4-associated syndromes and the previously published transcriptome analyses of ALF transcription factors suggest that these factors are not redundant and each contributes uniquely to proper development