NM_000023.4:c.974C>T

Variant summary

Our verdict is Uncertain significance. The variant received 1 ACMG points: 2P and 1B. PM2BP4

The NM_000023.4(SGCA):​c.974C>T​(p.Ala325Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000512 in 1,560,980 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Synonymous variant affecting the same amino acid position (i.e. A325A) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000050 ( 0 hom. )

Consequence

SGCA
NM_000023.4 missense

Scores

8
11

Clinical Significance

Uncertain significance criteria provided, single submitter U:2

Conservation

PhyloP100: 1.17

Publications

1 publications found
Variant links:
Genes affected
SGCA (HGNC:10805): (sarcoglycan alpha) This gene encodes a component of the dystrophin-glycoprotein complex (DGC), which is critical to the stability of muscle fiber membranes and to the linking of the actin cytoskeleton to the extracellular matrix. Its expression is thought to be restricted to striated muscle. Mutations in this gene result in type 2D autosomal recessive limb-girdle muscular dystrophy. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Oct 2008]
SGCA Gene-Disease associations (from GenCC):
  • autosomal recessive limb-girdle muscular dystrophy
    Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
  • autosomal recessive limb-girdle muscular dystrophy type 2D
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Myriad Women’s Health, Laboratory for Molecular Medicine, Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 1 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.35383993).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SGCANM_000023.4 linkc.974C>T p.Ala325Val missense_variant Exon 8 of 10 ENST00000262018.8 NP_000014.1
SGCANM_001135697.3 linkc.602C>T p.Ala201Val missense_variant Exon 6 of 8 NP_001129169.1
SGCANR_135553.2 linkn.801C>T non_coding_transcript_exon_variant Exon 7 of 9

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
SGCAENST00000262018.8 linkc.974C>T p.Ala325Val missense_variant Exon 8 of 10 1 NM_000023.4 ENSP00000262018.3

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152230
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
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:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00
AC:
0
AN:
169780
AF XY:
0.00
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 FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000497
AC:
7
AN:
1408750
Hom.:
0
Cov.:
30
AF XY:
0.00000431
AC XY:
3
AN XY:
695658
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
32208
American (AMR)
AF:
0.00
AC:
0
AN:
37164
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25322
East Asian (EAS)
AF:
0.00
AC:
0
AN:
36836
South Asian (SAS)
AF:
0.00
AC:
0
AN:
80042
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
49798
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5704
European-Non Finnish (NFE)
AF:
0.00000646
AC:
7
AN:
1083312
Other (OTH)
AF:
0.00
AC:
0
AN:
58364
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.496
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:
0.00000657
AC:
1
AN:
152230
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74364
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41454
American (AMR)
AF:
0.00
AC:
0
AN:
15290
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5196
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10624
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68046
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
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
Bravo
AF:
0.0000113
ExAC
AF:
0.00000858
AC:
1

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 2D Uncertain:2
Jul 06, 2021
Natera, Inc.
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Dec 06, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces alanine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 325 of the SGCA protein (p.Ala325Val). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with SGCA-related conditions. ClinVar contains an entry for this variant (Variation ID: 572580). 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 not expected to disrupt SGCA protein function. 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
0.11
BayesDel_addAF
Uncertain
0.10
D
BayesDel_noAF
Benign
-0.090
CADD
Benign
22
DANN
Uncertain
0.98
DEOGEN2
Uncertain
0.79
.;D;T
Eigen
Benign
-0.16
Eigen_PC
Benign
-0.017
FATHMM_MKL
Uncertain
0.79
D
LIST_S2
Benign
0.73
T;T;T
M_CAP
Uncertain
0.28
D
MetaRNN
Benign
0.35
T;T;T
MetaSVM
Uncertain
0.53
D
MutationAssessor
Benign
1.8
.;L;.
PhyloP100
1.2
PrimateAI
Uncertain
0.55
T
PROVEAN
Benign
-1.3
N;N;N
REVEL
Uncertain
0.39
Sift
Benign
0.088
T;T;T
Sift4G
Benign
0.50
T;T;T
Polyphen
0.087
B;B;.
Vest4
0.39
MutPred
0.48
.;Loss of disorder (P = 0.0956);.;
MVP
0.98
MPC
0.34
ClinPred
0.70
D
GERP RS
4.4
Varity_R
0.076
gMVP
0.28
Mutation Taster
=81/19
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.010
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: rs780200261; hg19: chr17-48248018; API