GLB1 C521C - GET-Evidence

Note: This variant has not been sufficiently evaluated by a GET-Evidence editor.

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GLB1 C521C

(GLB1 Cys521Cys)

Short summary

Expression studies show that the variant reduces activity of b-galactosidase to 25% of wild type. There is disagreement in the literature whether this variant causes GM1-gangliosidosis.

Variant evidence
Computational -
Functional -
Case/Control -
Familial -
Clinical importance
Severity -
Treatability -
Penetrance -


Insufficiently evaluated pathogenic

(The "insufficiently evaluated" qualifier is assigned automatically based on the above evidence and importance scores.)

Inheritance pattern


Summary of published research, and additional commentary


Allele frequency

  • None available.


Silva CM, Severini MH, Sopelsa A, Coelho JC, Zaha A, d'Azzo A, Giugliani R. Six novel beta-galactosidase gene mutations in Brazilian patients with GM1-gangliosidosis. Hum Mutat. 1999;13(5):401-9. PubMed PMID: 10338095.

This variant is found with an allelic frequency of 0.04 in a population in Brazil. The authors classify it as a benign polymorphism.

Caciotti A, Donati MA, Boneh A, d'Azzo A, Federico A, Parini R, Antuzzi D, Bardelli T, Nosi D, Kimonis V, Zammarchi E, Morrone A. Role of beta-galactosidase and elastin binding protein in lysosomal and nonlysosomal complexes of patients with GM1-gangliosidosis. Hum Mutat. 2005 Mar;25(3):285-92. PubMed PMID: 15714521.

This variant is identified in a homozygous fashion in a Moroccan female with GM1-gangliosidosis. Onset was at 27y. Expression studies showed that the mutation led to a decrease in protein expression to 25% of wild type, mimicking the blood work of the patient. Frequency in 200 control chromosomes was less than 0.01.


Other external references

    Web search results (0 hits -- see all)

Other in silico analyses

  • NBLOSUM100 score = –14
  • GET-Evidence autoscore = 2

Edit history

Gene search

"GENE" or "GENE A123C":

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