Scientific Publications

Lorem ipsum dolor sit amet, consectetur adipiscing elit. Duis blandit elit metus, mattis consectetur eros fermentum id. Cras lorem purus, finibus vel aliquam ac, porta in libero. Cras lorem purus, finibus vel aliquam ac, porta in libero.

  • Results Per Page

4 Results

2021

Abnormal SCID Newborn Screening and Spontaneous Recovery Associated with a Novel Haploinsufficiency IKZF1 Mutation

Kuehn HS, Gloude NJ, Dimmock D, Tokita M, Wright M, Rosenzweig SD, Collins C.

J Clin Immunol. 2021 Apr 14. doi: 10.1007/s10875-021-01035-1. Online ahead of print. ABSTRACT PURPOSE: IKAROS, encoded by IKZF1, is a member of the IKAROS family of zinc-finger transcription factors playing critical roles in lymphocyte development, differentiation, and tumor suppression. Several studies demonstrated that IKZF1 mutations affecting DNA binding or homo-/hetero-dimerization are mostly associated with common variable immunodeficiency, combined immunodeficiency, or hematologic manifestations. Herein we report a likely de novo, nonsense IKZF1 mutation (p.C182*) in a baby with low T cell receptor excision circles (TREC) identified by newborn screening testing for severe combined immunodeficiency. The patient also presented a profound B cell deficiency at birth. METHODS: Genetic, functional, immunologic, and clinical outcome data associated with this patient and her mutation were evaluated. RESULTS: Mutant p.C182* was detected in the cytoplasm of the patient’s primary cells, in contrast to wild type (WT) IKAROS protein, only detected in the nucleus. Functional in vitro assessments revealed that p.C182* was less stable than WT IKAROS protein and failed to bind to its target DNA binding sequence and dimerize with WT IKAROS protein, resulting in impaired pericentromeric targeting and transcriptional repression by means of haploinsufficiency. During follow-up, while a spontaneous recovery of TREC and T cells was observed, B cells improved but not to sustained normal ranges. CONCLUSIONS: Patients with IKAROS-associated diseases can present with SCID-like TREC values through newborn screening testing. IKZF1 mutations should be added to the low TREC differential, although spontaneous recovery has to be considered. PMID:33855675 | DOI:10.1007/s10875-021-01035-1

April 15, 2021

2020

Second Tier Molecular Genetic Testing in Newborn Screening for Pompe Disease: Landscape and Challenges

Smith LD, Bainbridge MN, Parad RB, Bhattacharjee A

Int J Neonatal Screen. 2020 Jun;6(2):32. doi: 10.3390/ijns6020032. Epub 2020 Apr 5. ABSTRACT Pompe disease (PD) is screened by a two tier newborn screening (NBS) algorithm, the first tier of which is an enzymatic assay performed on newborn dried blood spots (DBS). As first tier enzymatic screening tests have false positive results, an immediate second tier test on the same sample is critical in resolving newborn health status. Two methodologies have been proposed for second tier testing: (a) measurement of enzymatic activities such as of Creatine/Creatinine over alpha-glucosidase ratio, and (b) DNA sequencing (a molecular genetics approach), such as targeted next generation sequencing. (tNGS). In this review, we discuss the tNGS approach, as well as the challenges in providing second tier screening and follow-up care. While tNGS can predict genotype-phenotype effects when known, these advantages may be diminished when the variants are novel, of unknown significance or not discoverable by current test methodologies. Due to the fact that criticisms of screening algorithms that utilize tNGS are based on perceived complexities, including variant detection and interpretation, we clarify the actual limitations and present the rationale that supports optimizing a molecular genetic testing approach with tNGS. Second tier tNGS can benefit clinical decision-making through the use of the initial NBS DBS punch and rapid turn-around time methodology for tNGS, that includes copy number variant analysis, variant effect prediction, and variant ‘cut-off’ tools for the reduction of false positive results. The availability of DNA sequence data will contribute to the improved understanding of genotype-phenotype associations and application of treatment. The ultimate goal of second tier testing should enable the earliest possible diagnosis for the earliest initiation of the most effective clinical interventions in infants with PD. PMID:32352041 | PMC:PMC7189780 | DOI:10.3390/ijns6020032

May 1, 2020

2021

Postmortem whole-genome sequencing on a dried blood spot identifies a novel homozygous SUOX variant causing isolated sulfite oxidase deficiency

Owen MJ, Lenberg J, Feigenbaum A, Gold J, Chau K, Bezares-Orin Z, Ding Y, Chowdhury S, Kingsmore SF. 

Cold Spring Harb Mol Case Stud. 2021 Jun 11;7(3):a006091. doi: 10.1101/mcs.a006091. Print 2021 Jun. ABSTRACT Rapid whole-genome sequencing (rWGS) has shown that genetic diseases are a common cause of infant mortality in neonatal intensive care units. Dried blood spots collected for newborn screening allow investigation of causes of infant mortality that were not diagnosed during life. Here, we present a neonate who developed seizures and encephalopathy on the third day of life that was refractory to antiepileptic medications. The patient died on day of life 16 after progressive respiratory failure and sepsis. The parents had lost two prior children after similar presentations, neither of whom had a definitive diagnosis. Postmortem rWGS of a dried blood spot identified a pathogenic homozygous frameshift variant in the SUOX gene associated with isolated sulfite oxidase deficiency (c.1390_1391del, p.Leu464GlyfsTer10). This case highlights that early, accurate molecular diagnosis has the potential to influence prenatal counseling and guide management in rare, genetic disorders and has added importance in cases of a strong family history and risk factors such as consanguinity. PMID:34117075 | DOI:10.1101/mcs.a006091

June 14, 2021
Infant MortalityrWGS

2020

Mortality in a neonate with molybdenum cofactor deficiency illustrates the need for a comprehensive rapid precision medicine system

Kingsmore SF, Ramchandar N, James K, Niemi AK, Feigenbaum A, Ding Y, Benson W, Hobbs C, Nahas S, Chowdhury S, Dimmock D. 

Cold Spring Harb Mol Case Stud. 2020 Feb 3;6(1):a004705. doi: 10.1101/mcs.a004705. Print 2020 Feb. ABSTRACT Neonatal encephalopathy with seizures is a presentation in which rapid whole-genome sequencing (rWGS) has shown clinical utility and improved outcomes. We report a neonate who presented on the third day of life with seizures refractory to antiepileptic medications and neurologic and computerized tomographic findings consistent with severe generalized brain swelling. rWGS revealed compound heterozygous variants in the molybdenum cofactor synthesis gene, type 1A (MOCS1 c.*7 + 5G > A and c.377G > A); a provisional diagnosis of molybdenum cofactor deficiency on day of life 4. An emergency investigational new drug application for intravenous replacement of the MOCS1 product, cyclic pyranopterin monophosphate, was considered, but felt unsuitable in light of the severity of disease and delay in the start of treatment. The patient died on day of life 9 despite having a precise molecular diagnosis within the first week of life. This case illustrates that an rWGS-based molecular diagnosis within the first week of life may be insufficient to improve outcomes. However, it did inform clinical decision-making with regard to resuscitation and predicted long-term outcome. We suggest that to achieve optimal reductions in morbidity and mortality, rWGS must be implemented within a comprehensive rapid precision medicine system (CRPM). Akin to newborn screening (NBS), CRPM will have onboarding, diagnosis, and precision medicine implementation components developed in response to patient and parental needs. Education of health-care providers in a learning model in which ongoing data analyses informs system improvement will be essential for optimal effectiveness of CRPM. PMID:32014857 | PMC:PMC6996516 | DOI:10.1101/mcs.a004705

February 5, 2020
Infant MortalityrWGS

Publications Question?

Contact Us About BeginNGS