rs372188878

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM1PM2

The NM_000231.3(SGCG):ā€‹c.670A>Gā€‹(p.Met224Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000397 in 1,613,600 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (ā˜…ā˜…). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. M224I) has been classified as Uncertain significance.

Frequency

Genomes: š‘“ 0.000039 ( 0 hom., cov: 31)
Exomes š‘“: 0.000040 ( 0 hom. )

Consequence

SGCG
NM_000231.3 missense

Scores

7
12

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 3.25
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 4 ACMG points.

PM1
In a chain Gamma-sarcoglycan (size 290) in uniprot entity SGCG_HUMAN there are 38 pathogenic changes around while only 8 benign (83%) in NM_000231.3
PM2
Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE UniProt
SGCGNM_000231.3 linkuse as main transcriptc.670A>G p.Met224Val missense_variant 7/8 ENST00000218867.4
LOC107984585XR_001749787.2 linkuse as main transcriptn.2808+838T>C intron_variant, non_coding_transcript_variant

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Appris UniProt
SGCGENST00000218867.4 linkuse as main transcriptc.670A>G p.Met224Val missense_variant 7/81 NM_000231.3 P1
SACSENST00000682775.1 linkuse as main transcriptc.2186-8613T>C intron_variant
SACSENST00000683210.1 linkuse as main transcriptc.2186-31485T>C intron_variant
SACSENST00000684325.1 linkuse as main transcriptc.*104+838T>C intron_variant, NMD_transcript_variant

Frequencies

GnomAD3 genomes
AF:
0.0000395
AC:
6
AN:
151962
Hom.:
0
Cov.:
31
show subpopulations
Gnomad AFR
AF:
0.0000242
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:
0.0000735
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000199
AC:
5
AN:
251320
Hom.:
0
AF XY:
0.0000221
AC XY:
3
AN XY:
135840
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000440
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000397
AC:
58
AN:
1461638
Hom.:
0
Cov.:
32
AF XY:
0.0000358
AC XY:
26
AN XY:
727128
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000522
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.0000395
AC:
6
AN:
151962
Hom.:
0
Cov.:
31
AF XY:
0.00
AC XY:
0
AN XY:
74230
show subpopulations
Gnomad4 AFR
AF:
0.0000242
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000735
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000386
Hom.:
0
Bravo
AF:
0.0000227
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.0000330
AC:
4
EpiCase
AF:
0.0000545
EpiControl
AF:
0.00

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Autosomal recessive limb-girdle muscular dystrophy type 2C Uncertain:3
Uncertain significance, no assertion criteria providedclinical testingNatera, Inc.Nov 11, 2019- -
Uncertain significance, criteria provided, single submitterclinical testingRevvity Omics, RevvityNov 19, 2019- -
Uncertain significance, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpAug 27, 2021This sequence change replaces methionine with valine at codon 224 of the SGCG protein (p.Met224Val). The methionine residue is moderately conserved and there is a small physicochemical difference between methionine and valine. This variant is present in population databases (rs372188878, ExAC 0.006%). This variant has not been reported in the literature in individuals affected with SGCG-related conditions. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be tolerated. 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. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.13
BayesDel_addAF
Uncertain
0.043
T
BayesDel_noAF
Uncertain
-0.070
CADD
Benign
11
DANN
Benign
0.46
DEOGEN2
Uncertain
0.64
D
Eigen
Benign
-0.45
Eigen_PC
Benign
-0.40
FATHMM_MKL
Benign
0.69
D
LIST_S2
Benign
0.70
T
M_CAP
Benign
0.043
D
MetaRNN
Uncertain
0.45
T
MetaSVM
Uncertain
-0.12
T
MutationAssessor
Uncertain
2.4
M
MutationTaster
Benign
0.51
D;D;D
PrimateAI
Benign
0.42
T
PROVEAN
Benign
-0.95
N
REVEL
Uncertain
0.41
Sift
Benign
0.16
T
Sift4G
Benign
0.31
T
Polyphen
0.27
B
Vest4
0.28
MVP
0.83
MPC
0.14
ClinPred
0.32
T
GERP RS
3.0
Varity_R
0.21
gMVP
0.50

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

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs372188878; hg19: chr13-23894867; API