Diagnostic Use of Genome Sequencing in Patients With 11p15.5 Imprinting Disorder Features: A Pilot Study.

To assess the suitability of genome sequencing (GS) as the second step in the diagnostics of patients with the features of 11p15.5-associated imprinting disorders (ImpDis: Silver-Russell syndrome [SRS], Beckwith-Wiedemann syndrome [BWS]), we performed short-read GS in patients negatively tested for imprinting disturbances. Obtaining a genetic diagnosis for patients with the features of these syndromes is challenging due to the clinical and molecular heterogeneity and overlap, and many patients remain undiagnosed after the currently suggested stepwise diagnostic workup.

Closing the Gap - Detection of 5q-Spinal Muscular Atrophy by Short-Read Next-Generation Sequencing and Unexpected Results in a Diagnostic Patient Cohort.

Background: The importance of early diagnosis of 5q-Spinal muscular atrophy (5q-SMA) has heightened as early intervention can significantly improve clinical outcomes. In 96% of cases, 5q-SMA is caused by a homozygous deletion of SMN1. Around 4 % of patients carry a SMN1 deletion and a single-nucleotide variant (SNV) on the other allele.

Clonal Elimination of the Pathogenic Allele as Diagnostic Pitfall in -Associated Neuropathy.

Background: Heterozygous gain-of-function variants in are associated with ataxia-pancytopenia syndrome (ATXPC) and monosomy 7 myelodysplasia and leukemia syndrome-1 (M7MLS1). Association with peripheral neuropathy has rarely been described.

Methods: Whole-exome sequencing (WES) from DNA extracted from peripheral blood was performed in a 10-year-old female presenting with demyelinating neuropathy, her similarly affected mother and the unaffected maternal grandparents.

Novel phenotype with prominent cerebellar oculomotor dysfunction in spastic paraplegia type 39.

Objectives: The term hereditary spastic paraplegia comprises an ever-expanding array of neurological disorders with distinct aetiologies. Spastic paraplegia gene 39 is one of the many genetically defined types with features of other organs and neurological systems in addition to paraspasticity. We describe a large kindred with a novel clinical phenotype as, in addition to spastic paraplegia, affected subjects suffered from a prominent cerebellar oculomotor dysfunction with two hitherto undescribed mutations of PNPLA6.

Newborn Screening for SMA - Can a Wait-and-See Strategy be Responsibly Justified in Patients With Four SMN2 Copies?

Background: Early treatment after genetic newborn screening (NBS) for SMA significantly improves outcomes in infantile SMA. However, there is no consensus in the SMA treatment community about early treatment initiation in patients with four copies of SMN2.

Objective: Approach to a responsible treatment strategy for SMA patients with four SMN2 copies detected in newborn screening.

Genetic pain loss disorders.

Genetic pain loss includes congenital insensitivity to pain (CIP), hereditary sensory neuropathies and, if autonomic nerves are involved, hereditary sensory and autonomic neuropathy (HSAN). This heterogeneous group of disorders highlights the essential role of nociception in protecting against tissue damage. Patients with genetic pain loss have recurrent injuries, burns and poorly healing wounds as disease hallmarks.

Hereditary Sensory and Autonomic Neuropathy: A Case Series of Six Children.

Objectives: Hereditary sensory and autonomic neuropathy (HSAN) is a group of rare disorders affecting the sensory and autonomic neurons. Herein, we describe the clinical and genetic profile of six children with HSAN.

Methods: Hospital records of six children diagnosed with HSAN over 7 years (2011-2018) were retrieved.

Diagnosing small fiber neuropathy in clinical practice: a deep phenotyping study.

Background And Aims: Small fiber neuropathy (SFN) is increasingly suspected in patients with pain of uncertain origin, and making the diagnosis remains a challenge lacking a diagnostic gold standard.

Methods: In this case-control study, we prospectively recruited 86 patients with a medical history and clinical phenotype suggestive of SFN. Patients underwent neurological examination, quantitative sensory testing (QST), and distal and proximal skin punch biopsy, and were tested for pain-associated gene loci.

Newborn screening for spinal muscular atrophy in Germany: clinical results after 2 years.

Background: Spinal muscular atrophy (SMA) is the most common neurodegenerative disease in childhood. Since motor neuron injury is usually not reversible, early diagnosis and treatment are essential to prevent major disability. Our objective was to assess the impact of genetic newborn screening for SMA on outcome.

Molecular pathophysiology of human MICU1 deficiency.

Aims: MICU1 encodes the gatekeeper of the mitochondrial Ca uniporter, MICU1 and biallelic loss-of-function mutations cause a complex, neuromuscular disorder in children. Although the role of the protein is well understood, the precise molecular pathophysiology leading to this neuropaediatric phenotype has not been fully elucidated. Here we aimed to obtain novel insights into MICU1 pathophysiology.

The genetic landscape of axonal neuropathies in the middle-aged and elderly: Focus on .

Objective: To test the hypothesis that monogenic neuropathies such as Charcot-Marie-Tooth disease (CMT) contribute to frequent but often unexplained neuropathies in the elderly, we performed genetic analysis of 230 patients with unexplained axonal neuropathies and disease onset ≥35 years.

Methods: We recruited patients, collected clinical data, and conducted whole-exome sequencing (WES; n = 126) and single-gene sequencing (n = 104). We further queried WES repositories for variants and measured blood levels of the -encoded protein neprilysin.

Need for a precise molecular diagnosis in Beckwith-Wiedemann and Silver-Russell syndrome: what has to be considered and why it is important.

Molecular diagnostic testing of the 11p15.5-associated imprinting disorders Silver-Russell and Beckwith-Wiedemann syndrome (SRS, BWS) is challenging due to the broad spectrum of molecular defects and their mosaic occurrence. Additionally, the decision on the molecular testing algorithm is hindered by their clinical heterogeneity.

Differential diagnosis of vacuolar myopathies in the NGS era.

Altered autophagy accompanied by abnormal autophagic (rimmed) vacuoles detectable by light and electron microscopy is a common denominator of many familial and sporadic non-inflammatory muscle diseases. Even in the era of next generation sequencing (NGS), late-onset vacuolar myopathies remain a diagnostic challenge. We identified 32 adult vacuolar myopathy patients from 30 unrelated families, studied their clinical, histopathological and ultrastructural characteristics and performed genetic testing in index patients and relatives using Sanger sequencing and NGS including whole exome sequencing (WES).

Infants Diagnosed with Spinal Muscular Atrophy and 4 SMN2 Copies through Newborn Screening - Opportunity or Burden?

Although the value of newborn screening (NBS) for early detection and treatment opportunity in SMA patients is generally accepted, there is still an ongoing discussion about the best strategy in children with 4 and more copies of the SMN2 gene. This gene is known to be the most important but not the only disease modifier.In our SMA-NBS pilot project in Germany comprising 278,970 infants screened between January 2018 and November 2019 were 38 positive cases with a homozygous SMN1 deletion.

Paroxysmal tonic upgaze: A heterogeneous clinical condition responsive to carbonic anhydrase inhibition.

Background: Paroxysmal tonic upgaze (PTU), defined as an involuntary upward movement of the eyes, has been considered as a benign phenomenon but may also be associated with ataxia and developmental delay.

Methods: We report eight children with PTU; six of them also exhibiting symptoms of ataxia and/or developmental delay. Treatment with carbonic anhydrase inhibition was offered to children with persisting and/or severe forms.

Hereditary Neuropathies.

Background: Hereditary peripheral neuropathies constitute a large group of genetic diseases, with an overall prevalence of 1:2500. In recent years, the use of so-called next-generation sequencing (NGS) has led to the identification of many previously unknown involved genes and genetic defects that cause neuropathy. In this article, we review the procedures and utility of genetic evaluation for hereditary neurop - athies, while also considering the implications of the fact that causally directed treatment of these disorders is generally unavailable.

NSD1 duplication in Silver-Russell syndrome (SRS): molecular karyotyping in patients with SRS features.

Silver-Russell syndrome (SRS) is a growth retardation syndrome characterized by intrauterine and postnatal growth retardation, relative macrocephaly and protruding forehead, body asymmetry and feeding difficulties. Nearly 50% of cases show a hypomethylation in 11p15.5, in 10% maternal uniparental disomy of chromosome 7 is present.

EMQN best practice guidelines for the molecular genetic testing and reporting of chromosome 11p15 imprinting disorders: Silver-Russell and Beckwith-Wiedemann syndrome.

Molecular genetic testing for the 11p15-associated imprinting disorders Silver-Russell and Beckwith-Wiedemann syndrome (SRS, BWS) is challenging because of the molecular heterogeneity and complexity of the affected imprinted regions. With the growing knowledge on the molecular basis of these disorders and the demand for molecular testing, it turned out that there is an urgent need for a standardized molecular diagnostic testing and reporting strategy. Based on the results from the first external pilot quality assessment schemes organized by the European Molecular Quality Network (EMQN) in 2014 and in context with activities of the European Network of Imprinting Disorders (EUCID.

Autosomal dominant spinal muscular atrophy with lower extremity predominance: A recognizable phenotype of BICD2 mutations.

Introduction: Heterozygous BICD2 gene mutations cause a form of autosomal dominant spinal muscular atrophy with lower extremity predominance (SMALED).

Methods: We analyzed the BICD2 gene in a selected group of 25 index patients with neurogenic muscle atrophy.

Results: We identified 2 new BICD2 missense mutations, c.

Distally pronounced infantile spinal muscular atrophy with severe axonal and demyelinating neuropathy associated with the S230L mutation of SMN1.

Two Croatian siblings with atypical clinical findings in the presence of SMN1 gene mutations are reported. The girl presented with delayed motor development and weakness in hands and feet in her first year of life. She never stood or walked and developed scoliosis and joint contractures during childhood.