-
Frontiers in Genetics 2023Alpha-mannosidosis caused by mutations in the gene is a rare genetic disorder characterized by physical abnormalities and intellectual disabilities. The objective of...
Alpha-mannosidosis caused by mutations in the gene is a rare genetic disorder characterized by physical abnormalities and intellectual disabilities. The objective of this study was to analyze the carrier frequency and estimated incidence of alpha-mannosidosis in East Asian populations, as limited data exists on its incidence in this group. In this study, a total of 125,748 exomes from the gnomAD database was analyzed. Additionally, 5,305 data from the KOVA and 1,722 data from the KRGDB, both representing Korean populations, were included. The global carrier frequency of alpha-mannosidosis in gnomAD was 0.23%; the highest carrier frequency was observed in the Finnish at 0.49%, and East Asians had the second highest carrier frequency at 0.30%. Globally, the approximate incidence of alpha-mannosidosis was calculated at 1 in 784,535, l in 166,801 Europeans (Finnish), and l in 431,689 East Asians. By integrating the data from the 8,936 Koreans in gnomAD Korean, KOVA and KRGDB, the carrier frequency of alpha-mannosidosis in the Korean population was 0.04% and estimated incidence was 1 in 19,963,024. This study is the first to investigate the carrier frequencies of alpha-mannosidosis in East Asians and Koreans, including specific subpopulations, utilizing gnomAD and the Korean genomic database. The variant spectrum of genes in East Asians showed significant differences compared to other ethnic groups. Our data provide valuable reference information for future investigations into alpha-mannosidosis, aiding in understanding the genetic diversity and specific variants associated with the condition in East Asian populations.
PubMed: 38107468
DOI: 10.3389/fgene.2023.1297543 -
Orphanet Journal of Rare Diseases Jun 2018α-mannosidosis is a rare, autosomal-recessive, lysosomal storage disease caused by a deficient activity of α-mannosidase. Typical symptoms include intellectual, motor...
BACKGROUND
α-mannosidosis is a rare, autosomal-recessive, lysosomal storage disease caused by a deficient activity of α-mannosidase. Typical symptoms include intellectual, motor and hearing impairment, facial coarsening, and musculoskeletal abnormalities. Ocular pathologies reported previously were mainly opacities of the cornea and lens, strabismus, and ocular motility disorders. However, retinal and optic nerve degeneration have been rarely described.
METHODS
We report ocular findings of 32 patients with α-mannosidosis. We particularly concentrated on retinal abnormalities which we supported by posterior segment examination, fundus photography, and Spectral-Domain optical coherence tomography (SD-OCT) imaging.
RESULTS
Tapeto-retinal degeneration with bone spicule formations in the peripheral retina or macular changes were seen in three patients (9.4%) on funduscopy; of these, two with optic nerve atrophy. Eight retinal images could be obtained by OCT or fundus photography; of these, six showed thinning of the outer retinal layers on OCT. Overall, optic nerve atrophy was seen in six patients (18.8%); of these, four with partial atrophy. Two patients had partial optic nerve atrophy with no retinal abnormalities on funduscopy. Cataract was seen in two (6.3%), corneal haze also in two patients (6.3%). Six patients (18.8%) had manifest strabismus, four (12.5%) nystagmus, and in five patients (15.6%) impaired smooth pursuit eye movements were seen.
CONCLUSION
Ocular pathologies are not exclusively confined to opacities of the cornea and lens or strabismus and ocular motility disorders but tapeto-retinal degeneration and optic nerve atrophy may be a common feature in α-mannosidosis. OCT technology helps detecting early outer retinal thinning which can progress with age and potentially leads to vision loss over time.
Topics: Adolescent; Adult; Child; Child, Preschool; Female; Humans; Infant; Male; Middle Aged; Nerve Degeneration; Optic Atrophy; Retina; Retinal Degeneration; Tomography, Optical Coherence; Young Adult; alpha-Mannosidosis
PubMed: 29859105
DOI: 10.1186/s13023-018-0829-z -
Orphanet Journal of Rare Diseases Aug 2020The Roma are a European ethnic minority threatened by several recessive diseases. Variants in MANBA cause a rare lysosomal storage disorder named beta-mannosidosis whose...
Variant c.2158-2A>G in MANBA is an important and frequent cause of hereditary hearing loss and beta-mannosidosis among the Czech and Slovak Roma population- evidence for a new ethnic-specific variant.
BACKGROUND
The Roma are a European ethnic minority threatened by several recessive diseases. Variants in MANBA cause a rare lysosomal storage disorder named beta-mannosidosis whose clinical manifestation includes deafness and mental retardation. Since 1986, only 23 patients with beta-mannosidosis and biallelic MANBA variants have been described worldwide.
RESULTS
We now report on further 10 beta-mannosidosis patients of Roma origin from eight families in the Czech and Slovak Republics with hearing loss, mental retardation and homozygous pathogenic variants in MANBA. MANBA variant c.2158-2A>G screening among 345 anonymized normal hearing controls from Roma populations revealed a carrier/heterozygote frequency of 3.77%. This is about 925 times higher than the frequency of this variant in the gnomAD public database and classifies the c.2158-2A>G variant as a prevalent, ethnic-specific variant causing hearing loss and mental retardation in a homozygous state. The frequency of heterozygotes/carriers is similar to another pathogenic variant c.71G>A (p.W24*) in GJB2, regarded as the most frequent variant causing deafness in Roma populations.
CONLCUSION
Beta-mannosidosis, due to a homozygous c.2158-2A>G MANBA variant, is an important and previously unknown cause of hearing loss and mental retardation among Central European Roma.
Topics: Czech Republic; Deafness; Ethnicity; Hearing Loss; Humans; Minority Groups; Roma; Slovakia; beta-Mannosidosis
PubMed: 32847582
DOI: 10.1186/s13023-020-01508-3 -
Biochimica Et Biophysica Acta Oct 1999Glycoproteinoses belong to the lysosomal storage disorders group. The common feature of these diseases is the deficiency of a lysosomal protein that is part of glycan... (Review)
Review
Glycoproteinoses belong to the lysosomal storage disorders group. The common feature of these diseases is the deficiency of a lysosomal protein that is part of glycan catabolism. Most of the lysosomal enzymes involved in the hydrolysis of glycoprotein carbohydrate chains are exo-glycosidases, which stepwise remove terminal monosaccharides. Thus, the deficiency of a single enzyme causes the blockage of the entire pathway and induces a storage of incompletely degraded substances inside the lysosome. Different mutations may be observed in a single disease and in all cases account for the nonexpression of lysosomal glycosidase activity. Different clinical phenotypes generally characterize a specific disorder, which rather must be described as a continuum in severity, suggesting that other biochemical or environmental factors influence the course of the disease. This review provides details on clinical features, genotype-phenotype correlations, enzymology and biochemical storage of four human glycoprotein lysosomal storage disorders, respectively alpha- and beta-mannosidosis, fucosidosis and alpha-N-acetylgalactosaminidase deficiency. Moreover, several animal disorders of glycoprotein metabolism have been found and constitute valuable models for the understanding of their human counterparts.
Topics: Animals; Carbohydrate Sequence; Congenital Disorders of Glycosylation; Disease Models, Animal; Fucosidosis; Glycoside Hydrolases; Hexosaminidases; Humans; Molecular Sequence Data; Phenotype; alpha-Mannosidosis; alpha-N-Acetylgalactosaminidase
PubMed: 10571005
DOI: 10.1016/s0925-4439(99)00077-0 -
Journal of Medical Genetics Feb 1986Chromosome 19 is currently the most fully mapped of the smaller chromosomes, with about 40 loci assigned to it (HGM8). Major inherited disorders on this chromosome... (Review)
Review
Chromosome 19 is currently the most fully mapped of the smaller chromosomes, with about 40 loci assigned to it (HGM8). Major inherited disorders on this chromosome include myotonic dystrophy and familial hypercholesterolaemia. Other loci include five blood groups, a cluster of apolipoprotein genes, and the receptors for insulin and polio virus. A number of cloned genes and random DNA sequences identify polymorphisms which, together with blood group and other protein polymorphisms, have been used to establish a framework for ordering the loci and estimating genetic distances. Hybrid cell lines allow loci to be assigned to one of eight different regions and a detailed genetic map of the chromosome will be possible in the near future.
Topics: ABO Blood-Group System; Apolipoproteins C; Apolipoproteins E; Chromosome Mapping; Chromosomes, Human, 6-12 and X; DNA Repair; Enzymes; Genes; Humans; Hypercholesterolemia; Myotonic Dystrophy; Neurofibromatosis 1; Polymorphism, Genetic; Proteins; alpha-Mannosidosis
PubMed: 3081724
DOI: 10.1136/jmg.23.1.2 -
Molecular Genetics and Metabolism Jul 2019Multiplex tandem mass spectrometry (MS/MS)-based enzyme activity assays for newborn screening (NBS) and diagnosis of lysosomal storage diseases (LSDs) in newborns, using...
Multiplex tandem mass spectrometry (MS/MS)-based enzyme activity assays for newborn screening (NBS) and diagnosis of lysosomal storage diseases (LSDs) in newborns, using dried blood spots (DBS) on newborn screening cards, have garnered much attention due to its sensitivity, high precision, and the capability to screen for an unprecedented number of diseases in a single assay. Herein we report the development of MS/MS-based enzyme assays for the diagnosis of α-mannosidosis and fucosidosis. These new protocols are able to distinguish untreated patients from random newborns, carriers and a post-bone marrow transplant patient. We have successfully multiplexed the α-mannosidosis assay with a multiplex MS/MS assay for the screening and diagnosis of other LSDs, namely Fabry, Pompe, MPS I, Gaucher, Niemann-Pick-A/B, and Krabbe diseases. Additionally, we also multiplexed the fucosidosis NBS assay with a 5-plex assay that tests for MPS-II, MPS-IIIB, MPS-IVA, MPS-VI and MPS-VII.
Topics: Enzyme Assays; Fucosidosis; Humans; Infant, Newborn; Lysosomal Storage Diseases; Neonatal Screening; Tandem Mass Spectrometry; alpha-Mannosidosis
PubMed: 31235216
DOI: 10.1016/j.ymgme.2019.05.016 -
The British Journal of Radiology Jan 2014Lysosomal storage diseases (LSDs) are a large group of genetic metabolic disorders that result in the accumulation of abnormal material, such as mucopolysaccharides,... (Review)
Review
Lysosomal storage diseases (LSDs) are a large group of genetic metabolic disorders that result in the accumulation of abnormal material, such as mucopolysaccharides, glycoproteins, amino acids and lipids, within cells. Since many LSDs manifest during infancy or early childhood, with potentially devastating consequences if left untreated, timely identification is imperative to prevent irreversible damage and early death. In this review, the key imaging features of the non-lipid or extralipid LSDs are examined and correlated with salient clinical manifestations and genetic information. Disorders are stratified based on the type of excess material causing tissue or organ dysfunction, with descriptions of the mucopolysaccharidoses, mucolipidoses, alpha-mannosidosis, glycogen storage disorder II and cystinosis. In addition, similarities and differences in radiological findings between each of these LSDs are highlighted to facilitate further recognition. Given the rare and extensive nature of the LSDs, mastery of their multiple clinical and radiological traits may seem challenging. However, an understanding of the distinguishing imaging characteristics of LSDs and their clinical correlates may allow radiologists to play a key role in the early diagnosis of these progressive and potentially fatal disorders.
Topics: Diagnosis, Differential; Glucuronidase; Humans; Lyases; Lysosomal Storage Diseases; Metabolism, Inborn Errors; Mucopolysaccharidosis I; Mucopolysaccharidosis II; Mucopolysaccharidosis III; Mucopolysaccharidosis IV; Mucopolysaccharidosis VI; Mucopolysaccharidosis VII
PubMed: 24234586
DOI: 10.1259/bjr.20130467 -
Molecular Genetics and Metabolism 2019Hereditary β-mannosidosis causing progressive lysosomal neuropathy and other clinical signs, has been previously described in humans, Nubian goats, and Salers cattle....
Hereditary β-mannosidosis causing progressive lysosomal neuropathy and other clinical signs, has been previously described in humans, Nubian goats, and Salers cattle. Here we report the clinicopathological, metabolic, and molecular genetic features of canine beta-mannosidase (MANBA, EC 3.2.1.25) deficiency. A 1-year-old male mix-breed dog from St. Kitts was presented with progressive stumbling, weakness, and regurgitation. Vacuolated lymphocytes were observed on the blood film. Postmortem findings included marked enlargement of nerves, megaesophagus, and internal hydrocephalus. Vacuolated macrophages, neurons, and secretory epithelial cells suggested an oligosaccharide storage disease. Plasma concentration of the β-mannosidosis specific oligosaccharide was approximately 75 fold that of controls. The plasma beta-mannosidase activity was severely reduced to ~5% of controls; five other lysosomal acid hydrolase activities were increased or within their normal reference interval. Genomic sequencing of this dog's MANBA gene identified a homozygous exonic five bp tandem duplication in the penultimate exon of the MANBA gene (c.2377_2381dupTATCA) which results in a reading frame shift, altering the subsequent amino acid sequence and creating a premature stop codon. The truncated beta-mannosidase enzyme is expected to be dysfunctional. This enzyme deficiency causes the accumulation of un-degraded oligosaccharides in cells, which affect the myelination of the peripheral and central nervous systems. This insertion was not encountered in 121 and 80-screened samples from dogs on St. Kitts (all were homozygous for wild-type) and Philadelphia region (wild-type), respectively. In conclusion, canine β-mannosidosis has similar clinicopathological features with some human patients, but milder signs than in ruminants and more severe than in knockout mice. Hence, dogs with β-mannosidosis could become a valuable disease model for the human disease.
Topics: Animals; Codon, Nonsense; DNA Mutational Analysis; Dog Diseases; Dogs; Exons; Male; Mutation; beta-Mannosidase; beta-Mannosidosis
PubMed: 31439511
DOI: 10.1016/j.ymgme.2019.08.002 -
SAGE Open Medical Case Reports 2021β-mannosidosis is a rare autosomal recessive lysosomal storage disease of glycoprotein catabolism caused by a deficiency of β-mannosidase. Clinical presentation...
β-mannosidosis is a rare autosomal recessive lysosomal storage disease of glycoprotein catabolism caused by a deficiency of β-mannosidase. Clinical presentation includes intellectual deficits, hearing loss, and recurrent respiratory infections. This report describes the dental treatment and follow-up dental care of a child with β-mannosidosis. The patient presented to the dental clinic at the age of 6 years with a localized swelling of his lower posterior teeth. Sickle cell disease and physical and mental developmental delays were noted. Clinical examination revealed a flattened nasal bridge, large head, short neck, open bite, gingival overgrowth, macroglossia, enlarged pulp chambers, and poor oral hygiene. Surgical treatment under general anesthesia included extractions, pulp therapy, and restorations. Four years later, the child returned with generalized gingival inflammation and new carious lesions. Periodontal and restorative treatment was provided, and a preventive dental regimen was established. Mannosidosis cases require complex dental procedures, consultations, and prompt follow-up.
PubMed: 34925842
DOI: 10.1177/2050313X211065796 -
Clinical Dysmorphology Jan 2024Alpha-mannosidosis (MIM #248500) is an ultra-rare autosomal recessive lysosomal storage disease with multi-system involvement and a wide phenotypic spectrum. Information...
Alpha-mannosidosis (MIM #248500) is an ultra-rare autosomal recessive lysosomal storage disease with multi-system involvement and a wide phenotypic spectrum. Information on long-term outcomes remains poor. We present the long-term outcomes (median, 19 years) of nine patients with alpha-mannosidosis, three females and six males, followed at a single center. The findings of the nine patients were collected from medical records and reported as mean ± SD or median, and range. The age of onset of the first symptoms ranged from 0-1 to 10 years. The diagnostic delay ranged from 2 to 22 years (median= 11 years). Coarse face, hearing, heart valves, joints, gait, language, dysarthria, psychiatric symptoms, I.Q., MRI, walking disabilities, orthopedic disturbances and surgeries showed a slow worsening over the decades. Our patients showed a slowly worsening progressive outcome over the decades. Psychiatric symptoms were present in 100% of our population and improved with the appropriate pharmacological intervention. This aspect requires attention when following up on these patients. Our description of the long-term evolution of alpha-mannosidosis patients may provide basic knowledge for understanding the effects of specific treatments.
Topics: Male; Female; Humans; Infant, Newborn; Infant; Child, Preschool; Child; Adolescent; Young Adult; Adult; Middle Aged; Aged; Aged, 80 and over; alpha-Mannosidosis; Delayed Diagnosis; Mental Disorders; Inheritance Patterns; Italy
PubMed: 37791705
DOI: 10.1097/MCD.0000000000000474