Total submissions: 3
Submitter | RCV | SCV | Clinical significance | Condition | Last evaluated | Review status | Method | Comment |
---|---|---|---|---|---|---|---|---|
Labcorp Genetics |
RCV003495104 | SCV004298096 | uncertain significance | Combined deficiency of sialidase AND beta galactosidase | 2023-11-24 | criteria provided, single submitter | clinical testing | This sequence change replaces glycine, which is neutral and non-polar, with serine, which is neutral and polar, at codon 457 of the CTSA protein (p.Gly457Ser). This variant is present in population databases (rs137854547, gnomAD 0.003%). This missense change has been observed in individual(s) with galactosialidosis (PMID: 8968752). ClinVar contains an entry for this variant (Variation ID: 385). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt CTSA protein function with a positive predictive value of 80%. Experimental studies have shown that this missense change affects CTSA function (PMID: 8968752). In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. |
Women's Health and Genetics/Laboratory Corporation of America, |
RCV003495104 | SCV005422911 | likely pathogenic | Combined deficiency of sialidase AND beta galactosidase | 2024-10-08 | criteria provided, single submitter | clinical testing | Variant summary: CTSA c.1315G>A (p.Gly439Ser) results in a non-conservative amino acid change in the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 1.2e-05 in 251436 control chromosomes. c.1315G>A has been reported in the literature in an individual affected with autosomal recessive Galactosialidosis with the second allele change not being detected (Zhou_1996). These report(s) do not provide unequivocal conclusions about association of the variant with Galactosialidosis. At least one publication reports experimental evidence evaluating an impact on protein function in patient-derived fibroblasts. The most pronounced variant effect results in a total loss of enzymatic activity due to attenuated phosphorylation and lysosomal localization and maturation of the mutant precursor (Zhou_1996). ClinVar contains an entry for this variant (Variation ID: 385). Based on the evidence outlined above, the variant was classified as likely pathogenic. |
OMIM | RCV000000416 | SCV000020560 | pathogenic | Galactosialidosis, early infantile | 1991-12-01 | no assertion criteria provided | literature only |