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Beta-D-mannosidosis(MANSB)

MedGen UID:
888408
Concept ID:
C4048196
Disease or Syndrome
Synonyms: Beta-mannosidase deficiency; Beta-Mannosidosis; Lysosomal beta-mannosidase deficiency; Mannosidosis, beta A, lysosomal; MANSB
SNOMED CT: Beta-D-mannosidosis (238047006); Beta-mannosidase deficiency (238047006)
Modes of inheritance:
Autosomal recessive inheritance
MedGen UID:
141025
Concept ID:
C0441748
Intellectual Product
Source: Orphanet
A mode of inheritance that is observed for traits related to a gene encoded on one of the autosomes (i.e., the human chromosomes 1-22) in which a trait manifests in individuals with two pathogenic alleles, either homozygotes (two copies of the same mutant allele) or compound heterozygotes (whereby each copy of a gene has a distinct mutant allele).
 
Gene (location): MANBA (4q24)
 
Monarch Initiative: MONDO:0009562
OMIM®: 248510
Orphanet: ORPHA118

Definition

Beta-mannosidosis (MANSB) is an autosomal recessive lysosomal storage disease of glycoprotein catabolism caused by a deficiency of lysosomal beta-mannosidase activity. The most severely affected patients show developmental delay and mental retardation, but there are differing levels of severity and some patients may have comparatively mild disease (Bedilu et al., 2002). The disorder was first described in goats (Jones and Dawson, 1981), who have a more severe neurodegenerative disorder than that seen in humans. [from OMIM]

Additional description

From MedlinePlus Genetics
Beta-mannosidosis is a rare inherited disorder affecting the way certain sugar molecules are processed in the body.

Signs and symptoms of beta-mannosidosis vary widely in severity, and the age of onset ranges from infancy to adulthood. Almost all individuals with beta-mannosidosis experience intellectual disability, and some have delayed motor development and seizures. Affected individuals may be prone to depression or have behavioral problems such as hyperactivity, impulsivity or aggression. People with beta-mannosidosis are often extremely introverted.

People with beta-mannosidosis may experience an increased risk of respiratory and ear infections, hearing loss, speech impairment, swallowing difficulties, poor muscle tone (hypotonia), and reduced sensation or other nervous system abnormalities in the extremities (peripheral neuropathy). They may also exhibit distinctive facial features and clusters of enlarged blood vessels forming small, dark red spots on the skin (angiokeratomas).  https://medlineplus.gov/genetics/condition/beta-mannosidosis

Clinical features

From HPO
Increased urinary disaccharide excretion
MedGen UID:
868660
Concept ID:
C4023062
Finding
Increased concentration of disaccharide in the urine.
Hearing impairment
MedGen UID:
235586
Concept ID:
C1384666
Disease or Syndrome
A decreased magnitude of the sensory perception of sound.
Aggressive behavior
MedGen UID:
1375
Concept ID:
C0001807
Individual Behavior
Behavior or an act aimed at harming a person, animal, or physical property (e.g., acts of physical violence; shouting, swearing, and using harsh language; slashing someone's tires).
Seizure
MedGen UID:
20693
Concept ID:
C0036572
Sign or Symptom
A seizure is an intermittent abnormality of nervous system physiology characterized by a transient occurrence of signs and/or symptoms due to abnormal excessive or synchronous neuronal activity in the brain.
Demyelinating peripheral neuropathy
MedGen UID:
82859
Concept ID:
C0270922
Disease or Syndrome
Demyelinating neuropathy is characterized by slow nerve conduction velocities with reduced amplitudes of sensory/motor nerve conduction and prolonged distal latencies.
Hyperactivity
MedGen UID:
98406
Concept ID:
C0424295
Finding
Hyperactivity is a condition characterized by constant and unusually high levels of activity, even in situations where it is deemed inappropriate.
Abnormal speech pattern
MedGen UID:
1853271
Concept ID:
C3687424
Finding
An abnormality in the sound (volume) or cadence (rate) of speech.
Intellectual disability
MedGen UID:
811461
Concept ID:
C3714756
Mental or Behavioral Dysfunction
Intellectual disability, previously referred to as mental retardation, is characterized by subnormal intellectual functioning that occurs during the developmental period. It is defined by an IQ score below 70.
Hypotonia
MedGen UID:
10133
Concept ID:
C0026827
Finding
Hypotonia is an abnormally low muscle tone (the amount of tension or resistance to movement in a muscle). Even when relaxed, muscles have a continuous and passive partial contraction which provides some resistance to passive stretching. Hypotonia thus manifests as diminished resistance to passive stretching. Hypotonia is not the same as muscle weakness, although the two conditions can co-exist.
Generalized hypotonia
MedGen UID:
346841
Concept ID:
C1858120
Finding
Generalized muscular hypotonia (abnormally low muscle tone).
Recurrent infections
MedGen UID:
65998
Concept ID:
C0239998
Finding
Increased susceptibility to infections.
Decreased circulating beta-mannosidase activity
MedGen UID:
1853122
Concept ID:
C5872910
Finding
Activity of the enzyme beta-mannosidase below the lower limit of normal. Beta-mannosidase is a lysosomal enzyme that catabolizes oligosaccharides.
Reduced tissue beta-mannosidase activity
MedGen UID:
1853286
Concept ID:
C5872954
Finding
Concentration or activity of beta-mannosidase (EC 3.2.1.25) below the lower limit of normal. Beta-mannosidas enzyme can be measured in multiple tissues including leukocytes and cultured fibroblasts.
Abnormal facial shape
MedGen UID:
98409
Concept ID:
C0424503
Finding
An abnormal morphology (form) of the face or its components.
Angiokeratoma
MedGen UID:
1542
Concept ID:
C0002985
Neoplastic Process
Angiokeratomas are hyperkeratotic papules that are characterized histologically by superficial ectatic (i.e., dilated) blood vessels with epidermal proliferation. Clinically, angiokeratoma presents as a small, raised, dark-red spot.
Tortuosity of conjunctival vessels
MedGen UID:
344487
Concept ID:
C1855391
Finding
The presence of an increased number of twists and turns of the conjunctival blood vessels.

Term Hierarchy

CClinical test,  RResearch test,  OOMIM,  GGeneReviews,  VClinVar  
  • CROGVBeta-D-mannosidosis

Professional guidelines

PubMed

Semeraro M, Sacchetti E, Deodato F, Coşkun T, Lay I, Catesini G, Olivieri G, Rizzo C, Boenzi S, Dionisi-Vici C
Orphanet J Rare Dis 2021 Jan 9;16(1):24. doi: 10.1186/s13023-020-01662-8. PMID: 33422100Free PMC Article
Huang R, Cathey S, Pollard L, Wood T
Clin Chem 2018 Dec;64(12):1772-1779. Epub 2018 Sep 10 doi: 10.1373/clinchem.2018.289645. PMID: 30201803
Taylor JF, Abbitt B, Walter JP, Davis SK, Jaques JT, Ochoa RF
Genetics 1993 Nov;135(3):855-68. doi: 10.1093/genetics/135.3.855. PMID: 8293984Free PMC Article

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