chr13-23295438-C-T

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2

The NM_000231.3(SGCG):​c.529C>T​(p.His177Tyr) variant causes a missense change. The variant allele was found at a frequency of 0.0000118 in 1,614,006 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. H177N) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000053 ( 0 hom., cov: 33)
Exomes 𝑓: 0.0000075 ( 0 hom. )

Consequence

SGCG
NM_000231.3 missense

Scores

4
11
4

Clinical Significance

Uncertain significance criteria provided, single submitter U:2

Conservation

PhyloP100: 4.10

Publications

1 publications found
Variant links:
Genes affected
SGCG (HGNC:10809): (sarcoglycan gamma) This gene encodes gamma-sarcoglycan, one of several sarcolemmal transmembrane glycoproteins that interact with dystrophin. The dystrophin-glycoprotein complex (DGC) spans the sarcolemma and is comprised of dystrophin, syntrophin, alpha- and beta-dystroglycans and sarcoglycans. The DGC provides a structural link between the subsarcolemmal cytoskeleton and the extracellular matrix of muscle cells. Defects in the encoded protein can lead to early onset autosomal recessive muscular dystrophy, in particular limb-girdle muscular dystrophy, type 2C (LGMD2C). [provided by RefSeq, Oct 2008]
SACS (HGNC:10519): (sacsin molecular chaperone) This gene encodes the sacsin protein, which includes a UbL domain at the N-terminus, a DnaJ domain, and a HEPN domain at the C-terminus. The gene is highly expressed in the central nervous system, also found in skin, skeletal muscles and at low levels in the pancreas. This gene includes a very large exon spanning more than 12.8 kb. Mutations in this gene result in autosomal recessive spastic ataxia of Charlevoix-Saguenay (ARSACS), a neurodegenerative disorder characterized by early-onset cerebellar ataxia with spasticity and peripheral neuropathy. The authors of a publication on the effects of siRNA-mediated sacsin knockdown concluded that sacsin protects against mutant ataxin-1 and suggest that "the large multi-domain sacsin protein is able to recruit Hsp70 chaperone action and has the potential to regulate the effects of other ataxia proteins" (Parfitt et al., PubMed: 19208651). A pseudogene associated with this gene is located on chromosome 11. Alternative splicing of this gene results in multiple transcript variants. [provided by RefSeq, May 2013]
SACS Gene-Disease associations (from GenCC):
  • Charlevoix-Saguenay spastic ataxia
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, G2P, Laboratory for Molecular Medicine, Labcorp Genetics (formerly Invitae), Myriad Women’s Health

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

PM2
Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SGCGNM_000231.3 linkc.529C>T p.His177Tyr missense_variant Exon 6 of 8 ENST00000218867.4 NP_000222.2 Q13326

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
SGCGENST00000218867.4 linkc.529C>T p.His177Tyr missense_variant Exon 6 of 8 1 NM_000231.3 ENSP00000218867.3 Q13326
SACSENST00000683210.1 linkc.2186-6195G>A intron_variant Intron 9 of 9 ENSP00000506739.1 A0A804HHS6

Frequencies

GnomAD3 genomes
AF:
0.0000526
AC:
8
AN:
152130
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.000193
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
GnomAD2 exomes
AF:
0.0000358
AC:
9
AN:
251462
AF XY:
0.0000368
show subpopulations
Gnomad AFR exome
AF:
0.000369
Gnomad AMR exome
AF:
0.0000867
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000753
AC:
11
AN:
1461758
Hom.:
0
Cov.:
30
AF XY:
0.00000825
AC XY:
6
AN XY:
727188
show subpopulations
African (AFR)
AF:
0.000119
AC:
4
AN:
33476
American (AMR)
AF:
0.000112
AC:
5
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26132
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39694
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53418
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1111896
Other (OTH)
AF:
0.0000331
AC:
2
AN:
60392
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
1
2
3
4
5
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:
0.0000525
AC:
8
AN:
152248
Hom.:
0
Cov.:
33
AF XY:
0.0000672
AC XY:
5
AN XY:
74448
show subpopulations
African (AFR)
AF:
0.000193
AC:
8
AN:
41546
American (AMR)
AF:
0.00
AC:
0
AN:
15284
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5176
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4822
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10604
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68026
Other (OTH)
AF:
0.00
AC:
0
AN:
2112
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.481
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

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:
0.0000658
Hom.:
0
Bravo
AF:
0.0000529
ESP6500AA
AF:
0.000227
AC:
1
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.0000412
AC:
5

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Autosomal recessive limb-girdle muscular dystrophy type 2C Uncertain:2
Dec 03, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces histidine, which is basic and polar, with tyrosine, which is neutral and polar, at codon 177 of the SGCG protein (p.His177Tyr). This variant is present in population databases (rs375592456, gnomAD 0.04%). This variant has not been reported in the literature in individuals affected with SGCG-related conditions. ClinVar contains an entry for this variant (Variation ID: 966298). 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 SGCG protein function with a positive predictive value of 80%. 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. -

Feb 21, 2020
Natera, Inc.
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.14
BayesDel_addAF
Uncertain
0.018
T
BayesDel_noAF
Uncertain
0.10
CADD
Pathogenic
27
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.88
D
Eigen
Uncertain
0.62
Eigen_PC
Uncertain
0.53
FATHMM_MKL
Uncertain
0.82
D
LIST_S2
Pathogenic
0.98
D
M_CAP
Uncertain
0.20
D
MetaRNN
Uncertain
0.62
D
MetaSVM
Pathogenic
0.99
D
MutationAssessor
Uncertain
2.9
M
PhyloP100
4.1
PrimateAI
Uncertain
0.77
T
PROVEAN
Uncertain
-2.6
D
REVEL
Pathogenic
0.71
Sift
Benign
0.040
D
Sift4G
Benign
0.13
T
Polyphen
1.0
D
Vest4
0.64
MVP
0.98
MPC
0.44
ClinPred
0.57
D
GERP RS
4.6
Varity_R
0.37
gMVP
0.60
Mutation Taster
=76/24
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
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: rs375592456; hg19: chr13-23869577; API