Guanidinoacetate methyltransferase (GAMT) deficiency is an autosomal recessive disorder of creatine biosynthesis due to pathogenic variants in the GAMT gene that lead to cerebral creatine deficiency and neurotoxic levels of guanidinoacetate. Untreated, GAMT deficiency is associated with hypotonia, significant intellectual disability, limited speech development, recurrent seizures, behavior problems, and involuntary movements. The birth prevalence of GAMT deficiency is likely between 0.
View Article and Find Full Text PDFMucopolysaccharidosis type II (MPS II), also known as Hunter syndrome, is an X-linked condition caused by pathogenic variants in the iduronate-2-sulfatase gene. The resulting reduced activity of the enzyme iduronate-2-sulfatase leads to accumulation of glycosaminoglycans that can progressively affect multiple organ systems and impair neurologic development. In 2006, the US Food and Drug Administration approved idursulfase for intravenous enzyme replacement therapy for MPS II.
View Article and Find Full Text PDFTesting immunoreactive trypsinogen (IRT) is the first step in cystic fibrosis (CF) newborn screening. While high IRT is associated with CF, some cases are missed. This survey aimed to find factors associated with missed CF cases due to IRT levels below program cutoffs.
View Article and Find Full Text PDFPromising treatments for spinal muscular atrophy (SMA), the leading genetic cause of infant mortality, prompted calls for inclusion in newborn screening (NBS). In January 2018, the New England Newborn Screening Program (NENSP) began statewide screening for SMA using a tiered algorithm looking for the absence of Exon 7. When results from the first and second tier needed reconciliation, we developed and validated a third tier DNA sequencing assay to ensure the presence or absence of Exon 7.
View Article and Find Full Text PDFMassachusetts began newborn screening (NBS) for Spinal Muscular Atrophy (SMA) following the availability of new treatment options. The New England Newborn Screening Program developed, validated, and implemented a screening algorithm for the detection of SMA-affected infants who show absent Exon 7 by Real-Time™ quantitative PCR (qPCR). We screened 179,467 neonates and identified 9 SMA-affected infants, all of whom were referred to a specialist by day of life 6 (average and median 4 days of life).
View Article and Find Full Text PDFBackground: Massachusetts began newborn screening (NBS) for severe combined immunodeficiency (SCID) using measurement of T-cell receptor excision circles (TRECs) from dried blood spots.
Objective: We describe developments and outcomes from the first 10 years of this program (February 1, 2009, to January 31, 2019).
Methods: TREC values, diagnostic, and outcome data from all patients screened for SCID were evaluated.
We describe the first case of MAN2B2 deficiency in a patient with immune dysregulation, developmental delay, and stroke. Altered mannosylation profile was restored in patient cells upon transduction of wild-type MAN2B2.
View Article and Find Full Text PDFNewborn screening (NBS) identifies infants with rare conditions to prevent death or the onset of irreversible morbidities. Conditions on the Health and Human Services Secretary's Recommended Uniform Screening Panel have been adopted by most state NBS programs, providing a consistent approach for identification of affected newborns across the United States. Screen-positive newborns are identified and referred for confirmatory diagnosis and follow-up.
View Article and Find Full Text PDFThe secretary of the US Department of Health and Human Services in February 2016 recommended that X-linked adrenoleukodystrophy (X-ALD) be added to the recommended uniform screening panel for state newborn screening programs. This decision was informed by data presented on the accuracy of screening from New York, the only state that currently offers X-ALD newborn screening, and published and unpublished data showing health benefits of earlier treatment (hematopoietic stem cell transplantation and adrenal hormone replacement therapy) for the childhood cerebral form of X-ALD. X-ALD newborn screening also identifies individuals with later-onset disease, but poor genotype-phenotype correlation makes predicting health outcomes difficult and might increase the risk of unnecessary treatment.
View Article and Find Full Text PDFPrimary immunodeficiency diseases comprise a group of heterogeneous genetic defects that affect immune system development and/or function. Here we use in vitro differentiation of human induced pluripotent stem cells (iPSCs) generated from patients with different recombination-activating gene 1 (RAG1) mutations to assess T-cell development and T-cell receptor (TCR) V(D)J recombination. RAG1-mutants from severe combined immunodeficient (SCID) patient cells showed a failure to sustain progression beyond the CD3(--)CD4(-)CD8(-)CD7(+)CD5(+)CD38(-)CD31(-/lo)CD45RA(+) stage of T-cell development to reach the CD3(-/+)CD4(+)CD8(+)CD7(+)CD5(+)CD38(+)CD31(+)CD45RA(-) stage.
View Article and Find Full Text PDFUnlabelled: Newborn screening (NBS) is intended to identify congenital conditions prior to the onset of symptoms in order to provide early intervention that leads to improved outcomes. NBS is a public health success, providing reduction in mortality and improved developmental outcomes for screened conditions. However, it is less clear to what extent newborn screening achieves the long-term goals relating to improved health, growth, development and function.
View Article and Find Full Text PDFBackground: The Department of Health and Human Services (HHS) Advisory Committee on Heritable Disorders in Newborns and Children ("Advisory Committee") makes recommendations to the HHS Secretary regarding addition of new conditions to the national Recommended Uniform Screening Panel for newborns. The Advisory Committee's decision-making process includes assessing the net benefit of screening for nominated conditions, informed by systematic evidence reviews generated by an independent Condition Review Workgroup. The evidence base regarding harms associated with screening for specific conditions is often more limited than that for benefits.
View Article and Find Full Text PDFBackground Combined immunodeficiencies are marked by inborn errors of T-cell immunity in which the T cells that are present are quantitatively or functionally deficient. Impaired humoral immunity is also common. Patients have severe infections, autoimmunity, or both.
View Article and Find Full Text PDFImportance: Newborn screening for severe combined immunodeficiency (SCID) using assays to detect T-cell receptor excision circles (TRECs) began in Wisconsin in 2008, and SCID was added to the national recommended uniform panel for newborn screened disorders in 2010. Currently 23 states, the District of Columbia, and the Navajo Nation conduct population-wide newborn screening for SCID. The incidence of SCID is estimated at 1 in 100,000 births.
View Article and Find Full Text PDFThere is broad recognition of the need for population-based research to assess the safety and efficacy of newborn screening (NBS) for conditions that are not on current panels. However, prospective population-based research poses significant ethical, regulatory, and logistical challenges. In the context of NBS, there have been a variety of approaches that address parental decision-making in pilot studies of new screening tests or conditions.
View Article and Find Full Text PDFPurpose: The US Secretary of Health and Human Services provides guidance to state newborn screening programs about which conditions should be included in screening (i.e., the "Recommended Uniform Screening Panel").
View Article and Find Full Text PDFBackground: Combined immunodeficiency with multiple intestinal atresias (CID-MIA) is a rare hereditary disease characterized by intestinal obstructions and profound immune defects.
Objective: We sought to determine the underlying genetic causes of CID-MIA by analyzing the exomic sequences of 5 patients and their healthy direct relatives from 5 unrelated families.
Methods: We performed whole-exome sequencing on 5 patients with CID-MIA and 10 healthy direct family members belonging to 5 unrelated families with CID-MIA.
T-cell receptor excision circles (TRECs) are circular DNA molecules formed during rearrangement of the T-cell receptor (TCR) genes during lymphocyte development. Copy number of the junctional portion of the δRec-ψJα TREC, assessed by quantitative PCR (qPCR) using DNA from dried blood spots (DBS), is a biomarker for newly formed T cells and absent or low numbers of TRECs indicate SCID (severe combined immunodeficiency) or T lymphocytopenia. No quantitation standard for TRECs exists.
View Article and Find Full Text PDFNewborn screening is performed under public health authority, with analysis carried out primarily by public health laboratories or other centralized laboratories. Increasingly, opportunities to improve infant health will arise from including screening tests that are completed at the birth centers instead of in centralized laboratories, constituting a significant shift for newborn screening. This report summarizes a framework developed by the US Secretary of Health and Human Services Advisory Committee on Heritable Disorders in Newborns and Children based on a series of meetings held during 2011 and 2012.
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