rs137854541

Variant summary

Our verdict is Pathogenic. The variant received 11 ACMG points: 11P and 0B. PM2PP3PP5_Very_Strong

The NM_000308.4(CTSA):​c.146A>G​(p.Gln49Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000372 in 1,613,392 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 (★★).

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000027 ( 0 hom. )

Consequence

CTSA
NM_000308.4 missense

Scores

11
5
3

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:3

Conservation

PhyloP100: 8.86

Publications

4 publications found
Variant links:
Genes affected
CTSA (HGNC:9251): (cathepsin A) This gene encodes a member of the peptidase S10 family of serine carboxypeptidases. Alternative splicing results in multiple transcript variants, at least one of which encodes a preproprotein that is proteolytically processed to generate two chains that comprise the heterodimeric active enzyme. This enzyme possesses deamidase, esterase and carboxypeptidase activities and acts as a scaffold in the lysosomal multienzyme complex. Mutations in this gene are associated with galactosialidosis. [provided by RefSeq, Nov 2015]
CTSA Gene-Disease associations (from GenCC):
  • galactosialidosis
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: G2P, Labcorp Genetics (formerly Invitae), Genomics England PanelApp, Orphanet, ClinGen, Illumina

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 11 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP3
Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.
PP5
Variant 20-45891714-A-G is Pathogenic according to our data. Variant chr20-45891714-A-G is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 377.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
CTSANM_000308.4 linkc.146A>G p.Gln49Arg missense_variant Exon 2 of 15 ENST00000646241.3 NP_000299.3
CTSANM_001127695.3 linkc.146A>G p.Gln49Arg missense_variant Exon 2 of 15 NP_001121167.1
CTSANM_001167594.3 linkc.146A>G p.Gln49Arg missense_variant Exon 2 of 14 NP_001161066.2
CTSANR_133656.2 linkn.191A>G non_coding_transcript_exon_variant Exon 2 of 15

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CTSAENST00000646241.3 linkc.146A>G p.Gln49Arg missense_variant Exon 2 of 15 NM_000308.4 ENSP00000493613.2

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152184
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000654
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.000193
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:
0.00000274
AC:
4
AN:
1461208
Hom.:
0
Cov.:
35
AF XY:
0.00
AC XY:
0
AN XY:
726912
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.0000447
AC:
2
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
52746
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1112008
Other (OTH)
AF:
0.0000331
AC:
2
AN:
60388
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.488
Heterozygous variant carriers
0
1
1
2
2
3
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:
0.0000131
AC:
2
AN:
152184
Hom.:
0
Cov.:
32
AF XY:
0.0000269
AC XY:
2
AN XY:
74348
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41454
American (AMR)
AF:
0.0000654
AC:
1
AN:
15284
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.000193
AC:
1
AN:
5192
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4836
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10622
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68006
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.625
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome 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
Alfa
AF:
0.0000341
Hom.:
0
Bravo
AF:
0.0000189

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Combined deficiency of sialidase AND beta galactosidase Pathogenic:3
Jan 11, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces glutamine, which is neutral and polar, with arginine, which is basic and polar, at codon 67 of the CTSA protein (p.Gln67Arg). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with galactosialidosis (PMID: 8514852, 18396002, 26259553). This variant is also known as Q49R. ClinVar contains an entry for this variant (Variation ID: 377). 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: 8514852). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may create or strengthen a splice site. In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. -

Jun 01, 1993
OMIM
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:literature only

- -

Jul 25, 2023
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: CTSA c.146A>G (p.Gln49Arg) results in a conservative amino acid change in the encoded protein sequence. Three of five in-silico tools predict a damaging effect of the variant on protein function. The variant was absent in 249136 control chromosomes (gnomAD). c.146A>G has been reported in the literature in individuals affected with Galactosialidosis (Shimmoto_1993, Hossain_2016, Matsumoto_2008). These data indicate that the variant is likely to be associated with disease. At least one publication reports experimental evidence evaluating an impact on protein function, finding that cells with the variant protein lacked carboxypeptidase, alpha-neuraminidase, and beta-galactosidase activity (Shimmoto_1993). The following publications have been ascertained in the context of this evaluation (PMID: 8514852, 26259553, 18396002). No submitters have cited clinical-significance assessments for this variant to ClinVar after 2014. Based on the evidence outlined above, the variant was classified as pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.86
BayesDel_addAF
Pathogenic
0.41
D
BayesDel_noAF
Pathogenic
0.34
CADD
Pathogenic
34
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.62
D;.;D;D;D;D
Eigen
Pathogenic
0.90
Eigen_PC
Pathogenic
0.81
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Pathogenic
1.0
D;D;.;.;D;D
M_CAP
Uncertain
0.28
D
MetaRNN
Pathogenic
0.98
D;D;D;D;D;D
MetaSVM
Pathogenic
0.90
D
MutationAssessor
Pathogenic
3.8
.;.;H;H;.;H
PhyloP100
8.9
PrimateAI
Benign
0.46
T
PROVEAN
Uncertain
-2.5
N;N;.;N;.;D
REVEL
Pathogenic
0.87
Sift
Uncertain
0.011
D;D;.;D;.;D
Sift4G
Benign
0.074
T;T;.;T;T;T
Polyphen
1.0
.;.;D;D;.;D
Vest4
0.81
MutPred
0.94
.;.;Gain of MoRF binding (P = 0.0236);Gain of MoRF binding (P = 0.0236);Gain of MoRF binding (P = 0.0236);Gain of MoRF binding (P = 0.0236);
MVP
0.97
MPC
1.2
ClinPred
1.0
D
GERP RS
5.4
PromoterAI
-0.0057
Neutral
Varity_R
0.91
gMVP
0.87
Mutation Taster
=8/92
disease causing (ClinVar)

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.65
Details are displayed if max score is > 0.2
DS_DG_spliceai
0.65
Position offset: 0

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

Publications

Other links and lift over

dbSNP: rs137854541; hg19: chr20-44520353; API