rs118204441

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PM1PM2PM5PP3_StrongPP5_Very_Strong

The NM_000512.5(GALNS):​c.280C>T​(p.Arg94Cys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000155 in 1,613,480 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R94L) has been classified as Likely pathogenic.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000016 ( 0 hom. )

Consequence

GALNS
NM_000512.5 missense

Scores

14
4
1

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:6

Conservation

PhyloP100: 2.43

Publications

26 publications found
Variant links:
Genes affected
GALNS (HGNC:4122): (galactosamine (N-acetyl)-6-sulfatase) This gene encodes N-acetylgalactosamine-6-sulfatase which is a lysosomal exohydrolase required for the degradation of the glycosaminoglycans, keratan sulfate, and chondroitin 6-sulfate. Sequence alterations including point, missense and nonsense mutations, as well as those that affect splicing, result in a deficiency of this enzyme. Deficiencies of this enzyme lead to Morquio A syndrome, a lysosomal storage disorder. [provided by RefSeq, Jul 2008]
GALNS Gene-Disease associations (from GenCC):
  • mucopolysaccharidosis type 4A
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: G2P, ClinGen, Labcorp Genetics (formerly Invitae), Orphanet, Genomics England PanelApp

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ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 18 ACMG points.

PM1
In a hotspot region, there are 7 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 17 uncertain in NM_000512.5
PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr16-88841935-C-A is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 1048177.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.987
PP5
Variant 16-88841936-G-A is Pathogenic according to our data. Variant chr16-88841936-G-A is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 651205.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
GALNSNM_000512.5 linkc.280C>T p.Arg94Cys missense_variant Exon 3 of 14 ENST00000268695.10 NP_000503.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
GALNSENST00000268695.10 linkc.280C>T p.Arg94Cys missense_variant Exon 3 of 14 1 NM_000512.5 ENSP00000268695.5

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152208
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000241
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD4 exome
AF:
0.0000164
AC:
24
AN:
1461272
Hom.:
0
Cov.:
31
AF XY:
0.0000151
AC XY:
11
AN XY:
726890
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33474
American (AMR)
AF:
0.00
AC:
0
AN:
44638
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26120
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39684
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86132
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53304
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000207
AC:
23
AN:
1111792
Other (OTH)
AF:
0.00
AC:
0
AN:
60360
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.471
Heterozygous variant carriers
0
1
3
4
6
7
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152208
Hom.:
0
Cov.:
33
AF XY:
0.00
AC XY:
0
AN XY:
74366
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41450
American (AMR)
AF:
0.00
AC:
0
AN:
15278
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5202
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4828
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10628
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68032
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.575
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0
EpiCase
AF:
0.000109
EpiControl
AF:
0.0000594

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:6
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Mucopolysaccharidosis, MPS-IV-A Pathogenic:5
Nov 07, 2021
Genome-Nilou Lab
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Sep 16, 2021
Revvity Omics, Revvity
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Dec 19, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces arginine, which is basic and polar, with cysteine, which is neutral and slightly polar, at codon 94 of the GALNS protein (p.Arg94Cys). This variant is present in population databases (no rsID available, gnomAD 0.01%). This missense change has been observed in individuals with mucopolysaccharidosis type IVa (PMID: 10814710, 23876334, 29731656). ClinVar contains an entry for this variant (Variation ID: 651205). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is expected to disrupt GALNS protein function with a positive predictive value of 95%. Experimental studies have shown that this missense change affects GALNS function (PMID: 7795586, 10814710). This variant disrupts the p.Arg94 amino acid residue in GALNS. Other variant(s) that disrupt this residue have been observed in individuals with GALNS-related conditions (PMID: 7795586, 9298823, 10814710, 23876334, 29731656), which suggests that this may be a clinically significant amino acid residue. For these reasons, this variant has been classified as Pathogenic. -

Feb 01, 2021
Laboratory of Diagnosis and Therapy of Lysosomal Disorders, University of Padova
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:research

In vitro and vivo functional studies supportive of a damaging effect on the gene product (low to null enzymatic activity in homozygotes; low to null in vitro enzymatic activity; PS3_moderate); the prevalence of the variant in affected individuals is significantly increased compared with the prevalence in controls (PS4_strong); very low frequency in gnomAD v2.1.1 (PM2_moderate); multiple lines of computational evidence support a deleterious effect on the gene (PP3_supporting) -

May 07, 2024
Fulgent Genetics, Fulgent Genetics
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not provided Pathogenic:1
Feb 11, 2025
GeneDx
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Published functional studies demonstrate a damaging effect on enzyme activity (PMID: 8826435); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Not observed at significant frequency in large population cohorts (gnomAD); This variant is associated with the following publications: (PMID: 25501214, 34542925, 22940367, 25287660, 7795586, 34387910, 29731656, 25545067, 24726177, 23876334, 16287098, 9375852, 31188588, 33728253, 37106005, 8826435, 30094185) -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.53
BayesDel_addAF
Pathogenic
0.55
D
BayesDel_noAF
Pathogenic
0.55
CADD
Pathogenic
32
DANN
Pathogenic
1.0
DEOGEN2
Pathogenic
0.94
D;.
Eigen
Pathogenic
0.73
Eigen_PC
Uncertain
0.60
FATHMM_MKL
Uncertain
0.92
D
LIST_S2
Pathogenic
0.99
D;D
M_CAP
Pathogenic
0.87
D
MetaRNN
Pathogenic
0.99
D;D
MetaSVM
Pathogenic
1.0
D
MutationAssessor
Pathogenic
4.1
H;.
PhyloP100
2.4
PrimateAI
Uncertain
0.75
T
PROVEAN
Pathogenic
-7.5
D;D
REVEL
Pathogenic
0.98
Sift
Pathogenic
0.0
D;D
Sift4G
Pathogenic
0.0
D;.
Polyphen
1.0
D;.
Vest4
0.99
MutPred
0.94
Loss of MoRF binding (P = 0.0085);.;
MVP
1.0
MPC
0.59
ClinPred
1.0
D
GERP RS
4.3
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.96
gMVP
0.97
Mutation Taster
=4/96
disease causing (ClinVar)

Splicing

Name
Calibrated prediction
Score
Prediction
Splicevardb
2.0
SpliceAI score (max)
0.0
Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

Other links and lift over

dbSNP: rs118204441; hg19: chr16-88908344; COSMIC: COSV51940717; COSMIC: COSV51940717; API