Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 85
Filter
1.
Bioanalysis ; 15(23): 1421-1437, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37847061

ABSTRACT

Background: A biomarker profile was evaluated longitudinally in patients with Fabry disease switched from enzyme-replacement therapy (ERT) to migalastat. Methods: 16 Gb3 isoforms and eight lyso-Gb3 analogues were analyzed in plasma and urine by LC-MS/MS at baseline and at three different time points in naive participants and participants switching from either agalsidase α or ß to migalastat. Results: 29 adult participants were recruited internationally (seven centers). The Mainz Severity Score Index and mean biomarker levels remained stable (p ≥ 0.05) over a minimum of 12 months compared with baseline following the treatment switch. Conclusion: In this cohort of patients with Fabry disease with amenable mutations, in the short term, a switch from ERT to migalastat did not have a marked effect on the average biomarker profile.


Subject(s)
Fabry Disease , Adult , Humans , Fabry Disease/drug therapy , Fabry Disease/genetics , Chromatography, Liquid , Tandem Mass Spectrometry , 1-Deoxynojirimycin/therapeutic use , Biomarkers
3.
Hum Mol Genet ; 32(15): 2422-2440, 2023 07 20.
Article in English | MEDLINE | ID: mdl-37129502

ABSTRACT

The recognition that cytosolic mitochondrial DNA (mtDNA) activates cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING) innate immune signaling has unlocked novel disease mechanisms. Here, an uncharacterized variant predicted to affect TOP1MT function, P193L, was discovered in a family with multiple early onset autoimmune diseases, including Systemic Lupus Erythematosus (SLE). Although there was no previous genetic association between TOP1MT and autoimmune disease, the role of TOP1MT as a regulator of mtDNA led us to investigate whether TOP1MT could mediate the release of mtDNA to the cytosol, where it could then activate the cGAS-STING innate immune pathway known to be activated in SLE and other autoimmune diseases. Through analysis of cells with reduced TOP1MT expression, we show that loss of TOP1MT results in release of mtDNA to the cytosol, which activates the cGAS-STING pathway. We also characterized the P193L variant for its ability to rescue several TOP1MT functions when expressed in TOP1MT knockout cells. We show that the P193L variant is not fully functional, as its re-expression at high levels was unable to rescue mitochondrial respiration deficits, and only showed partial rescue for other functions, including repletion of mtDNA replication following depletion, nucleoid size, steady state mtDNA transcripts levels and mitochondrial morphology. Additionally, expression of P193L at endogenous levels was unable to rescue mtDNA release-mediated cGAS-STING signaling. Overall, we report a link between TOP1MT and mtDNA release leading to cGAS-STING activation. Moreover, we show that the P193L variant has partial loss of function that may contribute to autoimmune disease susceptibility via cGAS-STING mediated activation of the innate immune system.


Subject(s)
Autoimmune Diseases , Lupus Erythematosus, Systemic , Humans , DNA, Mitochondrial/genetics , Immunity, Innate/genetics , Interferons , Nucleotidyltransferases/genetics , Nucleotidyltransferases/metabolism
4.
Mol Ther Methods Clin Dev ; 28: 262-271, 2023 Mar 09.
Article in English | MEDLINE | ID: mdl-36816757

ABSTRACT

The safety and efficacy of lentivirus-mediated gene therapy was recently demonstrated in five male patients with Fabry disease-a rare X-linked lysosomal storage disorder caused by GLA gene mutations that result in multiple end-organ complications. To evaluate the risks of clonal dominance and leukemogenesis, which have been reported in multiple gene therapy trials, we conducted a comprehensive DNA insertion site analysis of peripheral blood samples from the five patients in our gene therapy trial. We found that patients had a polyclonal integration site spectrum and did not find evidence of a dominant clone in any patient. Although we identified vector integrations near proto-oncogenes, these had low percentages of contributions to the overall pool of integrations and did not persist over time. Overall, we show that our trial of lentivirus-mediated gene therapy for Fabry disease did not lead to hematopoietic clonal dominance and likely did not elevate the risk of leukemogenic transformation.

5.
Article in English | MEDLINE | ID: mdl-36781206

ABSTRACT

Biallelic variants in the WFS1 gene are associated with Wolfram syndrome. However, recent publications document that heterozygous variants can lead to a variety of phenotypes, such as Wolfram-like syndrome or isolated features of Wolfram syndrome. In this case report, we present a male patient with a history of congenital cataracts and subjective complaints of muscle weakness. Clinical assessment demonstrated normal muscle strength, and genomic, biochemical, electrophysiologic, and muscle biopsy studies did not identify a potential cause of the proband's perceived muscle weakness. Whole-exome sequencing identified a novel de novo variant in the WFS1 gene (c.1243G > T), representing one of only several patients in the published literature with isolated congenital cataracts and a heterozygous WFS1 variant. The variety of phenotypes associated with heterozygous variants in WFS1 suggests that this gene should be considered as a cause of both dominant and biallelic/recessive forms of disease. Future research should focus on elucidating the mechanism(s) of disease and variable expressivity in WFS1 in order to improve our ability to provide patients and families with anticipatory guidance about the disease, including appropriate screening and medical interventions.


Subject(s)
Cataract , Wolfram Syndrome , Humans , Male , Cataract/genetics , Heterozygote , Mutation , Pedigree , Phenotype , Wolfram Syndrome/genetics , Wolfram Syndrome/diagnosis
6.
Curr Probl Cardiol ; 48(2): 101476, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36328338

ABSTRACT

Given the inherent complexities of Fabry disease (FD) and evolving landscape of cardiovascular clinical management, there is no established ideal clinical care model for these patients. We identified clinical factors predictive of increased risk of major adverse cardiac events (MACE) in patients with FD targeted to improve clinical outcomes. Ninety-five patients studied over a median follow-up time of 6.3 years, and 26 patients reached the composite endpoint with a high prevalence of heart failure and cerebrovascular events and no cardiac-related mortality. Patients with MACE had worse health-related quality of life scores. Hypertrophy and presence of myocardial fibrosis increase risk of MACE by 4-5 times, and dyslipidemia increases risk of MACE by 3 times. Early Fabry-specific treatment and close monitoring of comorbidities reduce cardiac complications and mortality. These findings highlight the importance of comprehensive multidisciplinary management to help improve outcomes in FD patients.


Subject(s)
Fabry Disease , Heart Diseases , Heart Failure , Humans , Fabry Disease/complications , Fabry Disease/therapy , Fabry Disease/epidemiology , Quality of Life , Magnetic Resonance Imaging , Heart Failure/complications
7.
Genet Med ; 25(6): 100314, 2023 06.
Article in English | MEDLINE | ID: mdl-36305855

ABSTRACT

PURPOSE: This study aimed to define the genotypic and phenotypic spectrum of reversible acute liver failure (ALF) of infancy resulting from biallelic pathogenic TRMU variants and determine the role of cysteine supplementation in its treatment. METHODS: Individuals with biallelic (likely) pathogenic variants in TRMU were studied within an international retrospective collection of de-identified patient data. RESULTS: In 62 individuals, including 30 previously unreported cases, we described 47 (likely) pathogenic TRMU variants, of which 17 were novel, and 1 intragenic deletion. Of these 62 individuals, 42 were alive at a median age of 6.8 (0.6-22) years after a median follow-up of 3.6 (0.1-22) years. The most frequent finding, occurring in all but 2 individuals, was liver involvement. ALF occurred only in the first year of life and was reported in 43 of 62 individuals; 11 of whom received liver transplantation. Loss-of-function TRMU variants were associated with poor survival. Supplementation with at least 1 cysteine source, typically N-acetylcysteine, improved survival significantly. Neurodevelopmental delay was observed in 11 individuals and persisted in 4 of the survivors, but we were unable to determine whether this was a primary or a secondary consequence of TRMU deficiency. CONCLUSION: In most patients, TRMU-associated ALF was a transient, reversible disease and cysteine supplementation improved survival.


Subject(s)
Liver Failure, Acute , Liver Failure , Adolescent , Child , Child, Preschool , Humans , Infant , Young Adult , Acetylcysteine/therapeutic use , Liver Failure/drug therapy , Liver Failure/genetics , Liver Failure, Acute/drug therapy , Liver Failure, Acute/genetics , Mitochondrial Proteins/genetics , Mutation , Retrospective Studies , tRNA Methyltransferases/genetics
8.
Clin Nutr ESPEN ; 51: 461-469, 2022 10.
Article in English | MEDLINE | ID: mdl-36184243

ABSTRACT

BACKGROUND & AIMS: Mitochondrial diseases (MITO) are a large group of rare genetic conditions that manifest in high-energy organ systems and impair mitochondrial oxidative phosphorylation. Therapeutic management often involves the use of dietary supplements and special dietary patterns. METHODS: A questionnaire assessing dietary patterns and supplement use was administered to diagnosed patients or their surrogate caregivers through various MITO-related patient and advocacy organizations and social media internationally from March to September 2021. Secondary outcomes assessed information available to participants regarding supplements, and factors influencing use, knowledge, and adherence to dietary supplements. Supplements were classified using standard criteria. A total of 236 responses were used for the analysis. RESULTS: The average number of supplements taken among patients was 7.0 (±5.0 SD) with over 70% reporting taking more than 4 supplements. Sixty percent of respondents reported dietary restrictions, while 14% were tube fed or parenterally fed. Uncertainty regarding supplement cost, use, and availability were a significant source of stress for most participants with 61% of patients reporting no financial coverage for supplementation and 45% reporting no coverage for special dietary needs. CONCLUSIONS: Adequate scientific evidence for the widespread use of dietary supplements in MITO is lacking. As a result, there is excessive supplementation in MITO that imposes significant stress on patients. Future studies are needed to evaluate the efficacy of specific supplements as well as special dietary patterns to enable physicians and pharmacists to provide evidence-based recommendations to patients to reduce symptoms, as well as the emotional and financial strain associated with supplement use.


Subject(s)
Dietary Supplements , Mitochondrial Diseases , Cross-Sectional Studies , Diet , Humans , Surveys and Questionnaires
9.
J Biol Chem ; 298(10): 102420, 2022 10.
Article in English | MEDLINE | ID: mdl-36030054

ABSTRACT

TOP1MT encodes a mitochondrial topoisomerase that is important for mtDNA regulation and is involved in mitochondrial replication, transcription, and translation. Two variants predicted to affect TOP1MT function (V1 - R198C and V2 - V338L) were identified by exome sequencing of a newborn with hypertrophic cardiomyopathy. As no pathogenic TOP1MT variants had been confirmed previously, we characterized these variants for their ability to rescue several TOP1MT functions in KO cells. Consistent with these TOP1MT variants contributing to the patient phenotype, our comprehensive characterization suggests that both variants had impaired activity. Critically, we determined neither variant was able to restore steady state levels of mitochondrial-encoded proteins nor to rescue oxidative phosphorylation when re-expressed in TOP1MT KO cells. However, we found the two variants behaved differently in some respects; while the V1 variant was more efficient in restoring transcript levels, the V2 variant showed better rescue of mtDNA copy number and replication. These findings suggest that the different TOP1MT variants affect distinct TOP1MT functions. Altogether, these findings begin to provide insight into the many roles that TOP1MT plays in the maintenance and expression of the mitochondrial genome and how impairments in this important protein may lead to human pathology.


Subject(s)
Cardiomyopathy, Hypertrophic , DNA Topoisomerases, Type I , Genome, Mitochondrial , Mitochondria , Humans , Infant, Newborn , Cardiomyopathy, Hypertrophic/genetics , DNA Topoisomerases, Type I/genetics , DNA Topoisomerases, Type I/metabolism , DNA, Mitochondrial/metabolism , Genetic Variation , Mitochondria/enzymology , Mitochondrial Proteins/genetics , Mitochondrial Proteins/metabolism
10.
Pharmacol Res Perspect ; 10(3): e00949, 2022 06.
Article in English | MEDLINE | ID: mdl-35417091

ABSTRACT

Fabry disease (FD) is a rare X-linked disorder of lipid metabolism, characterized by the accumulation of globotriaosylceramide (Gb3) due to defective the lysosomal enzyme, α-galactosidase. Gb3 deposits activate immune-mediated systemic inflammation, ultimately leading to life-threatening consequences in multiple organs such as the heart and kidneys. Enzyme replacement therapy (ERT), the standard of care, is less effective with advanced tissue injury and inflammation in patients with FD. Here, we showed that MCP-1 and TNF-α cytokine levels were almost doubled in plasma from ERT-treated FD patients. Chemokine receptor CCR2 surface expression was increased by twofold on monocytes from patients with low eGFR. We also observed an increase in IL12B transcripts in unstimulated peripheral blood mononuclear cells (PBMCs) over a 2-year period of continuous ERT. Apabetalone is a clinical-stage oral bromodomain and extra terminal protein inhibitor (BETi), which has beneficial effects on cardiovascular and kidney disease related pathways including inflammation. Here, we demonstrate that apabetalone, a BD2-selective BETi, dose dependently reduced the production of MCP-1 and IL-12 in stimulated PBMCs through transcriptional regulation of their encoding genes. Reactive oxygen species production was diminished by up to 80% in stimulated neutrophils following apabetalone treatment, corresponding with inhibition of NOX2 transcription. This study elucidates that inhibition of BET proteins by BD2-selective apabetalone alleviates inflammatory processes and oxidative stress in innate immune cells in general and in FD. These results suggest potential benefit of BD2-selective apabetalone in controlling inflammation and oxidative stress in FD, which will be further investigated in clinical trials.


Subject(s)
Fabry Disease , Cytokines/metabolism , Enzyme Replacement Therapy , Epigenesis, Genetic , Fabry Disease/drug therapy , Fabry Disease/genetics , Fabry Disease/metabolism , Humans , Immunity, Innate , Inflammation/drug therapy , Inflammation/genetics , Leukocytes, Mononuclear/metabolism , Quinazolinones
11.
Int J Mol Sci ; 23(6)2022 Mar 20.
Article in English | MEDLINE | ID: mdl-35328774

ABSTRACT

Human mitochondrial disorders impact tissues with high energetic demands and can be associated with cardiac muscle disease (cardiomyopathy) and early mortality. However, the mechanistic link between mitochondrial disease and the development of cardiomyopathy is frequently unclear. In addition, there is often marked phenotypic heterogeneity between patients, even between those with the same genetic variant, which is also not well understood. Several of the mitochondrial cardiomyopathies are related to defects in the maintenance of mitochondrial protein homeostasis, or proteostasis. This essential process involves the importing, sorting, folding and degradation of preproteins into fully functional mature structures inside mitochondria. Disrupted mitochondrial proteostasis interferes with mitochondrial energetics and ATP production, which can directly impact cardiac function. An inability to maintain proteostasis can result in mitochondrial dysfunction and subsequent mitophagy or even apoptosis. We review the known mitochondrial diseases that have been associated with cardiomyopathy and which arise from mutations in genes that are important for mitochondrial proteostasis. Genes discussed include DnaJ heat shock protein family member C19 (DNAJC19), mitochondrial import inner membrane translocase subunit TIM16 (MAGMAS), translocase of the inner mitochondrial membrane 50 (TIMM50), mitochondrial intermediate peptidase (MIPEP), X-prolyl-aminopeptidase 3 (XPNPEP3), HtraA serine peptidase 2 (HTRA2), caseinolytic mitochondrial peptidase chaperone subunit B (CLPB) and heat shock 60-kD protein 1 (HSPD1). The identification and description of disorders with a shared mechanism of disease may provide further insights into the disease process and assist with the identification of potential therapeutics.


Subject(s)
Cardiomyopathies , Mitochondrial Proteins , Cardiomyopathies/genetics , Cardiomyopathies/metabolism , HSP40 Heat-Shock Proteins/metabolism , Homeostasis , Humans , Mitochondria/metabolism , Mitochondrial Membrane Transport Proteins/metabolism , Mitochondrial Proteins/genetics , Mitochondrial Proteins/metabolism , Peptide Hydrolases/metabolism , Protein Transport , Proteostasis
13.
J Inherit Metab Dis ; 45(2): 366-376, 2022 03.
Article in English | MEDLINE | ID: mdl-34580891

ABSTRACT

The dilated cardiomyopathy with ataxia syndrome (DCMA) is an autosomal recessive mitochondrial disease caused by mutations in the DnaJ heat shock protein family (Hsp40) member C19 (DNAJC19) gene. DCMA or 3-methylglutaconic aciduria type V is globally rare, but the largest number of patients in the world is found in the Hutterite population of southern Alberta in Canada. We provide an update on phenotypic findings, natural history, pathological findings, and our clinical experience. We analyzed all available records for 43 patients diagnosed with DCMA between 2005 and 2015 at the Alberta Children's Hospital. All patients studied were Hutterite and homozygous for the causative DNAJC19 variant (c.130-1G>C, IVS3-1G>C) and had elevated levels of 3-methyglutaconic acid. We calculated a birth prevalence of 1.54 cases per 1000 total births in the Hutterite community. Children were small for gestational age at birth and frequently required supplemental nutrition (63%) or surgical placement of a gastrostomy tube (35%). Early mortality in this cohort was high (40%) at a median age of 13 months (range 4-294 months). Congenital anomalies were common as was dilated cardiomyopathy (50%), QT interval prolongation (83%), and developmental delay (95%). Tissue pathology was analyzed in a limited number of patients and demonstrated subendocardial fibrosis in the heart, macrovesicular steatosis and fibrosis in the liver, and structural abnormalities in mitochondria. This report provides clinical details for a cohort of children with DCMA and the first presentation of tissue pathology for this disorder. Despite sharing common genetic etiology and environment, the disease is highly heterogeneous for reasons that are not understood. DCMA is a clinically heterogeneous systemic mitochondrial disease with significant morbidity and mortality that is common in the Hutterite population of southern Alberta.


Subject(s)
Cardiomyopathy, Dilated , Mitochondrial Diseases , Ataxia/genetics , Cardiomyopathy, Dilated/diagnosis , Cardiomyopathy, Dilated/genetics , Cardiomyopathy, Dilated/metabolism , Cerebellar Ataxia , Fibrosis , Humans , Metabolism, Inborn Errors , Mitochondrial Diseases/complications , Phenotype , Syndrome
14.
J Neurol ; 269(4): 2162-2171, 2022 Apr.
Article in English | MEDLINE | ID: mdl-34537872

ABSTRACT

BACKGROUND AND OBJECTIVE: Pathogenic variants in KCNT1 have been associated with severe forms of epilepsy, typically sleep-related hypermotor epilepsy or epilepsy of infancy with migrating focal seizures. To show that pathogenic variants in KCNT1 can be associated with mild extra-frontal epilepsy, we report a KCNT1 family with a wide spectrum of phenotypes ranging from developmental and epileptic encephalopathy to mild focal epilepsy without cognitive regression and not consistent with sleep-related hypermotor epilepsy. METHODS: A large Canadian family of Caucasian descent including 9 affected family members was recruited. Family members were phenotyped by direct interview and review of existing medical records. Clinical epilepsy gene panel analysis and exome sequencing were performed. RESULTS: Phenotypic information was available for five family members of which two had developmental and epileptic encephalopathy and three had normal development and focal epilepsy with presumed extra-frontal onset. All three had predominantly nocturnal seizures that did not show hyperkinetic features. All three reported clusters of seizures at night with a feeling of being unable to breathe associated with gasping for air, choking and/or repetitive swallowing possibly suggesting insular or opercular involvement. Genetic analysis identified a heterozygous KCNT1 c.2882G > A, p.Arg961His variant that was predicted to be deleterious. DISCUSSION: This family demonstrates that the phenotypic spectrum associated with KCNT1 pathogenic variants is broader than previously assumed. Our findings indicate that variants in KCNT1 can be associated with mild focal epilepsy and should not be excluded during variant interpretation in such patients based solely on gene-disease validity.


Subject(s)
Epilepsies, Partial , Epileptic Syndromes , Nerve Tissue Proteins , Potassium Channels, Sodium-Activated , Canada , Epilepsies, Partial/genetics , Epileptic Syndromes/genetics , Humans , Mutation , Nerve Tissue Proteins/genetics , Phenotype , Potassium Channels, Sodium-Activated/genetics
15.
JPGN Rep ; 3(3): e210, 2022 Aug.
Article in English | MEDLINE | ID: mdl-37168626

ABSTRACT

Portosystemic shunts are used to treat portal hypertension arising from extrahepatic portal venous obstruction. They decompress the portal system by allowing intestinal blood to bypass the liver and enter directly into the systemic circulation. These shunts increase the risk of minimal hepatic encephalopathy and altered neurodevelopmental outcomes in affected children. Treatment options are limited and have been extrapolated from those used in cirrhosis. We describe the use of glycerol phenylbutyrate as an alternate management strategy. A 3-year-old boy underwent distal splenorenal shunt for refractory variceal bleeding secondary to portal hypertension. He had neurologic deterioration and hyperammonemia refractory to traditional management strategies. Glycerol phenylbutyrate was initiated and resulted in a sustained improvement in ammonia levels, behavior, and school performance. This case illustrates the successful use of glycerol phenylbutyrate in a noncirrhotic patient with Portosystemic shunt and minimal hepatic encephalopathy refractory to conventional management strategies.

16.
Drugs R D ; 21(4): 385-397, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34542871

ABSTRACT

BACKGROUND AND OBJECTIVE: Fabry disease, an X-linked lysosomal storage disorder characterized by absent or reduced alpha-galactosidase activity, is a lifelong disease that impairs patients' quality of life. Patients with Fabry disease have a considerably shortened lifespan, with mortality being mainly due to renal failure, cardiovascular disease, or cerebrovascular disease. Enzyme replacement therapy with agalsidase alfa has been shown to attenuate the renal, cardiovascular, and neuropathic disease progression associated with Fabry disease. The objective of this study was to investigate the safety of a new animal component-free version of agalsidase alfa. METHODS: A phase III/IV, open-label, single-arm, multicenter safety study was conducted in Canadian patients with Fabry disease between August 2011 and September 2017 as a regulatory requirement to assess the safety of agalsidase alfa produced using an animal component-free bioreactor process. Eligible patients had a documented diagnosis of Fabry disease and satisfied current Canadian guidelines for receiving enzyme replacement therapy for Fabry disease. Following treatment with animal component-free bioreactor-processed agalsidase alfa, treatment-emergent adverse events were monitored, and post hoc analyses of infusion-related reactions by antidrug antibody and neutralizing antibody statuses were conducted. The data were analyzed using descriptive statistics. RESULTS: A total of 167 patients (mean [standard deviation] age, 48.9 [14.8] years), including six pediatric patients (< 18 years of age), received at least one full or partial infusion of agalsidase alfa animal component-free. Fewer than 5% of treatment-emergent adverse events (212/4446) observed in 40 patients were reported as infusion-related reactions. Antidrug antibody and neutralizing antibody status did not affect the proportion of patients with infusion-related reactions. No clinically significant changes in vital signs were observed in patients over the course of the study. CONCLUSIONS: Long-term treatment with bioreactor-produced agalsidase alfa animal component-free did not reveal new safety signals in this population of Canadian patients with Fabry disease. The treatment-emergent adverse event profile was consistent with the clinical manifestations of the disease and the known safety profile of roller bottle-produced agalsidase alfa. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT01298141.


Subject(s)
Fabry Disease , alpha-Galactosidase , Animals , Bioreactors , Canada , Child , Enzyme Replacement Therapy , Fabry Disease/drug therapy , Humans , Isoenzymes , Middle Aged , Quality of Life , Recombinant Proteins/therapeutic use , Treatment Outcome , alpha-Galactosidase/adverse effects
17.
Pan Afr Med J ; 38: 111, 2021.
Article in English | MEDLINE | ID: mdl-33912281

ABSTRACT

Millions of patients, with suspected complex neurogenetic disorders, living in resource limited regions around the world have no access to genetic testing despite the rapidly expanding availability and decreasing costs of genetic testing in first world nations. The barriers to increasing availability of genetic testing in resource limited nations are multifactorial but can be attributed, in large part, to a lack of awareness of the power of genetic testing to lead to a rapid, cost-effective, diagnosis that potentially will have profound clinical implications on treatment and patient outcomes. We report our experience with whole exome sequencing (WES) done for the first time in 5 patients of African descent with a suspected neurogenetic disorder living in a resource limited setting on the Eastern Caribbean island of Barbados. A diagnostic pathogenic mutation was found in 3 patients in the SCN1A, STXBP1 and SCN4A, who clinically were diagnosed with Dravet syndrome, Lennox-Gastaut syndrome, paramytonia and seizures respectively. A variant of undetermined significance was found in a patient with global developmental delays, hypotonia, with abnormal eye movements. In one patient WES was non-diagnostic. This result highlights the high yield of WES in carefully selected patients with a neurologic disease and the need for increase access to genetic testing in resource limited settings globally.


Subject(s)
Exome Sequencing/methods , Genetic Testing/methods , Nervous System Diseases/diagnosis , Adult , Barbados , Child , Cost-Benefit Analysis , Genetic Testing/economics , Humans , Infant , Munc18 Proteins/genetics , Mutation , NAV1.1 Voltage-Gated Sodium Channel/genetics , NAV1.4 Voltage-Gated Sodium Channel/genetics , Nervous System Diseases/genetics , Nervous System Diseases/physiopathology , Exome Sequencing/economics , Young Adult
18.
Nat Commun ; 12(1): 1178, 2021 02 25.
Article in English | MEDLINE | ID: mdl-33633114

ABSTRACT

Enzyme and chaperone therapies are used to treat Fabry disease. Such treatments are expensive and require intrusive biweekly infusions; they are also not particularly efficacious. In this pilot, single-arm study (NCT02800070), five adult males with Type 1 (classical) phenotype Fabry disease were infused with autologous lentivirus-transduced, CD34+-selected, hematopoietic stem/progenitor cells engineered to express alpha-galactosidase A (α-gal A). Safety and toxicity are the primary endpoints. The non-myeloablative preparative regimen consisted of intravenous melphalan. No serious adverse events (AEs) are attributable to the investigational product. All patients produced α-gal A to near normal levels within one week. Vector is detected in peripheral blood and bone marrow cells, plasma and leukocytes demonstrate α-gal A activity within or above the reference range, and reductions in plasma and urine globotriaosylceramide (Gb3) and globotriaosylsphingosine (lyso-Gb3) are seen. While the study and evaluations are still ongoing, the first patient is nearly three years post-infusion. Three patients have elected to discontinue enzyme therapy.


Subject(s)
Fabry Disease/enzymology , Fabry Disease/therapy , Genetic Therapy/methods , Lentivirus/genetics , alpha-Galactosidase/genetics , alpha-Galactosidase/therapeutic use , Adult , Antigens, CD34 , Bone Marrow Cells , Fabry Disease/genetics , Genetic Vectors , Hematopoietic Stem Cells , Humans , Leukocytes , Male , Middle Aged , Trihexosylceramides/blood , Trihexosylceramides/urine
19.
Orphanet J Rare Dis ; 16(1): 92, 2021 02 18.
Article in English | MEDLINE | ID: mdl-33602299

ABSTRACT

BACKGROUND: Fractures in Gaucher disease type 1 (GD1) patients cause significant morbidity. Fracture risk may be decreased by enzyme replacement therapy (ERT) but not eliminated. When considering initiation of treatment, it is useful to know to what extent fixed patient-specific factors determine risk for future fractures beyond standard risk factors that change with time and treatment, such as decreased bone mineral density. We developed a tool called the GRAF score (Gaucher Risk Assessment for Fracture) that applies 5 widely available characteristics (sex, age at treatment initiation [ATI], time interval between diagnosis and treatment initiation, splenectomy status, history of pre-treatment bone crisis) and provides a practical method to assess future fracture risk when imiglucerase ERT is initiated. METHODS: Inclusion criteria: GD1 patients in the International Collaborative Gaucher Group Gaucher Registry as of September 2019 initially treated with alglucerase/imiglucerase; known splenectomy status; at least one skeletal assessment on treatment (3216 of 6422 patients). Data were analyzed by ATI group (< 18, ≥ 18 to < 50, or ≥ 50 years of age) using Cox proportional hazards regression with all 5 risk factors included in the multivariable model. A composite risk score was calculated by summing the contribution of each parameter weighted by the strength of its association (regression coefficient) with fracture risk. RESULTS: Patients were followed from the date of treatment initiation (or age 18 years for patients if treatment started earlier) to the date of first adult fracture (n = 288 first fracture endpoints), death, or end of follow-up. The GRAF score for each ATI group was associated with a 2.7-fold increased risk of adult fracture for each one-point increase (p < 0.02 for < 18 ATI, p < 0.0001 for ≥ 18 to < 50 ATI and ≥ 50 ATI). CONCLUSIONS: The GRAF score is a tool to be used with bone density and other modifiable, non-GD-specific risk factors (e.g. smoking, alcohol intake, frailty) to inform physicians and previously untreated GD1 patients about risk for a future fracture after starting imiglucerase regardless of whether there is an eventual switch to an alternative ERT or to substrate reduction therapy. GRAF can also help predict the extent that fracture risk increases if initiation of treatment is further delayed.


Subject(s)
Gaucher Disease , Adolescent , Adult , Enzyme Replacement Therapy , Gaucher Disease/complications , Gaucher Disease/drug therapy , Glucosylceramidase/therapeutic use , Humans , Risk Assessment , Risk Factors
20.
Front Cardiovasc Med ; 7: 584727, 2020.
Article in English | MEDLINE | ID: mdl-33304928

ABSTRACT

The diagnosis of cardiomyopathy states may benefit from machine-learning (ML) based approaches, particularly to distinguish those states with similar phenotypic characteristics. Three-dimensional myocardial deformation analysis (3D-MDA) has been validated to provide standardized descriptors of myocardial architecture and deformation, and may therefore offer appropriate features for the training of ML-based diagnostic tools. We aimed to assess the feasibility of automated disease diagnosis using a neural network trained using 3D-MDA to discriminate hypertrophic cardiomyopathy (HCM) from its mimic states: cardiac amyloidosis (CA), Anderson-Fabry disease (AFD), and hypertensive cardiomyopathy (HTNcm). 3D-MDA data from 163 patients (mean age 53.1 ± 14.8 years; 68 females) with left ventricular hypertrophy (LVH) of known etiology was provided. Source imaging data was from cardiac magnetic resonance (CMR). Clinical diagnoses were as follows: 85 HCM, 30 HTNcm, 30 AFD, and 18 CA. A fully-connected-layer feed-forward neural was trained to distinguish HCM vs. other mimic states. Diagnostic performance was compared to threshold-based assessments of volumetric and strain-based CMR markers, in addition to baseline clinical patient characteristics. Threshold-based measures provided modest performance, the greatest area under the curve (AUC) being 0.70. Global strain parameters exhibited reduced performance, with AUC under 0.64. A neural network trained exclusively from 3D-MDA data achieved an AUC of 0.94 (sensitivity 0.92, specificity 0.90) when performing the same task. This study demonstrates that ML-based diagnosis of cardiomyopathy states performed exclusively from 3D-MDA is feasible and can distinguish HCM from mimic disease states. These findings suggest strong potential for computer-assisted diagnosis in clinical practice.

SELECTION OF CITATIONS
SEARCH DETAIL
...