Generation and characterization of two iPSC lines derived from subjects with Free Sialic Acid Storage Disorder (FSASD).

Free sialic acid storage disorder (FSASD) is a rare, autosomal recessive, neurodegenerative disorder caused by biallelic mutations in SLC17A5, encoding the lysosomal transmembrane sialic acid exporter, SLC17A5. Defects in SLC17A5 lead to lysosomal accumulation of free sialic acid and other acid hexoses. The clinical spectrum of FSASD ranges from mild (Salla disease) to severe infantile forms.

Differential Tractography: A Biomarker for Neuronal Function in Neurodegenerative Disease.

GM1 gangliosidosis is an ultra-rare inherited neurodegenerative lysosomal storage disorder caused by biallelic mutations in the gene. GM1 is uniformly fatal and has no approved therapies, although clinical trials investigating gene therapy as a potential treatment for this condition are underway. Novel outcome measures or biomarkers demonstrating the longitudinal effects of GM1 and potential recovery due to therapeutic intervention are urgently needed to establish efficacy of potential therapeutics.

Central nervous system involvement in Erdheim-Chester disease: a magnetic resonance imaging study.

Purpose: To characterize brain MR imaging findings in a cohort of 58 patients with ECD and to evaluate relationship between these findings and the BRAF pathogenic variant.

Methods: ECD patients of any gender and ethnicity, aged 2-80 years, with biopsy-confirmed ECD were eligible to enroll in this study. Two radiologists experienced in evaluating ECD CNS disease activity reviewed MRI studies.

Patient-reported outcomes and functional assessments of patients with Alkaptonuria in a 3-year Nitisinone treatment trial.

Alkaptonuria is a rare disorder of tyrosine catabolism caused by deficiency of homogentisate 1,2-dioxygenase that leads to accumulation of homogentisic acid (HGA). Deposition of HGA-derived polymers in connective tissue causes progressive arthropathy of the spine and large joints, cardiac valvular disease, and genitourinary stones beginning in the fourth decade of life. Nitisinone, a potent inhibitor of the upstream enzyme, 4-hydroxyphenylpyruvate dioxygenase, dramatically reduces HGA production.

Impact of Food on the Oral Absorption of N-Acetyl-D-Mannosamine in Healthy Men and Women.

N-Acetyl-D-mannosamine (ManNAc) is an endogenous monosaccharide and precursor of N-acetylneuraminic acid (Neu5Ac), a critical sialic acid. ManNAc is currently under clinical development to treat GNE myopathy, a rare muscle-wasting disease. In this randomized, open-label, 2-sequence, crossover study, 16 healthy women and men were administered a single oral dose of ManNAc under fasting and fed conditions.

Plasma chitotriosidase enzyme activity as a novel therapeutic monitor for cysteamine treatment in nephropathic cystinosis: A retrospective validation study.

Background: Cystine-depleting therapy in nephropathic cystinosis is currently monitored via the white blood cell cystine assay, although its application and usefulness are limited by practical and technical issues. Therefore, alternative biomarkers that are widely available, more economical and less technically demanding, while reliably reflecting long-term adherence to cysteamine treatment, are desirable. Recently, we proposed chitotriosidase enzyme activity as a potential novel biomarker for the therapeutic monitoring of cysteamine treatment in cystinosis.

Calciphylaxis in POEMS syndrome: Case report.

POEMS Syndrome is a constellation of findings including Polyneuropathy, Organomegaly, Endocrinopathy, Monoclonal plasma cell disorder, and Skin changes. Calciphylaxis, a microangiopathy involving vascular calcification and thrombotic occlusions, occurs rarely in POEMS. We present a case of prominent calciphylaxis that antedated the diagnosis of POEMS.

Cellular Modeling of CLN6 with IPSC-derived Neurons and Glia.

Neuronal ceroid lipofuscinosis (NCL), type 6 (CLN6) is a neurodegenerative disorder associated with progressive neurodegeneration leading to dementia, seizures, and retinopathy. encodes a resident-ER protein involved in trafficking lysosomal proteins to the Golgi. CLN6p deficiency results in lysosomal dysfunction and deposition of storage material comprised of Nile Red lipids/proteolipids that include subunit C of the mitochondrial ATP synthase (SUBC).

Rare Disease Day: Amplifying voices, advocating hope.

Every year on February 28, the global community comes together to observe Rare Disease Day, a day dedicated to raising awareness and understanding for the millions of individuals who live with rare disorders. While individual rare diseases may seem uncommon, their collective impact is significant, affecting the lives of countless families and communities worldwide. This day serves as a crucial platform to amplify the voices of those affected, advocate for increased research and support, and inspire hope for a future where rare diseases can be prevented, diagnosed earlier, and effectively treated.

Skeletal involvement in Erdheim-Chester disease: Multimodality imaging features and association with the BRAF mutation.

Objective: The aim of this study was to characterize the distribution of skeletal involvement in Erdheim-Chester disease (ECD) by using radiography, computed tomography (CT), F-FDG positron emission tomography/computed tomography (PET/CT), and bone scans, as well as looking for associations with the BRAF mutation.

Material And Methods: Prospective study of 50 consecutive patients with biopsy-confirmed ECD who had radiographs, CT, F-FDG PET/CT, and Tc-99m MDP bone scans. At least two experienced radiologists with expertise in the relevant imaging studies analyzed the images.

Adult-onset neurodegeneration in XMEN disease.

Background: XMEN (X-linked immunodeficiency with magnesium defect, Epstein-Barr virus (EBV), and N-linked glycosylation defect) disease results from loss-of-function mutations in MAGT1, a protein that serves as a magnesium transporter and a subunit of the oligosaccharyltransferase (OST) complex. MAGT1 deficiency disrupts N-linked glycosylation, a critical regulator of immune function. XMEN results in recurrent EBV infections and a propensity for EBV-driven malignancies.

Pentanucleotide Repeat Insertions in RAI1 Cause Benign Adult Familial Myoclonic Epilepsy Type 8.

Background: Benign adult familial myoclonic epilepsy (BAFME) is an autosomal dominant disorder characterized by cortical tremors and seizures. Six types of BAFME, all caused by pentanucleotide repeat expansions in different genes, have been reported. However, several other BAFME cases remain with no molecular diagnosis.

International Undiagnosed Diseases Programs (UDPs): components and outcomes.

Over the last 15 years, Undiagnosed Diseases Programs have emerged to address the significant number of individuals with suspected but undiagnosed rare genetic diseases, integrating research and clinical care to optimize diagnostic outcomes. This narrative review summarizes the published literature surrounding Undiagnosed Diseases Programs worldwide, including thirteen studies that evaluate outcomes and two commentary papers. Commonalities in the diagnostic and research process of Undiagnosed Diseases Programs are explored through an appraisal of available literature.

Unmet needs in countries participating in the undiagnosed diseases network international: an international survey considering national health care and economic indicators.

Background: Patients, families, the healthcare system, and society as a whole are all significantly impacted by rare diseases (RDs). According to various classifications, there are currently up to 9,000 different rare diseases that have been recognized, and new diseases are discovered every month. Although very few people are affected by each uncommon disease individually, millions of people are thought to be impacted globally when all these conditions are considered.

Deep phenotyping of the neuroimaging and skeletal features in KBG syndrome: a study of 53 patients and review of the literature.

Background: KBG syndrome is caused by haploinsufficiency of and is characterised by macrodontia of upper central incisors, distinctive facial features, short stature, skeletal anomalies, developmental delay, brain malformations and seizures. The central nervous system (CNS) and skeletal features remain poorly defined.

Methods: CNS and/or skeletal imaging were collected from molecularly confirmed individuals with KBG syndrome through an international network.