rs35130237

Variant summary

Our verdict is Benign. The variant received -7 ACMG points: 2P and 9B. PM1BP4_StrongBP6BS2

The NM_000023.4(SGCA):​c.421C>A​(p.Arg141Ser) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000813 in 1,589,732 control chromosomes in the GnomAD database, including 4 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R141H) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.00058 ( 0 hom., cov: 32)
Exomes 𝑓: 0.00084 ( 4 hom. )

Consequence

SGCA
NM_000023.4 missense

Scores

1
6
12

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:9B:4

Conservation

PhyloP100: 0.159

Publications

4 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: Benign. The variant received -7 ACMG points.

PM1
In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 7 uncertain in NM_000023.4
BP4
Computational evidence support a benign effect (MetaRNN=0.016697764).
BP6
Variant 17-50168409-C-A is Benign according to our data. Variant chr17-50168409-C-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 197618.
BS2
High Homozygotes in GnomAdExome4 at 4 AR gene

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SGCANM_000023.4 linkc.421C>A p.Arg141Ser missense_variant Exon 5 of 10 ENST00000262018.8 NP_000014.1 Q16586-1A0A0S2Z4Q1
SGCANM_001135697.3 linkc.421C>A p.Arg141Ser missense_variant Exon 5 of 8 NP_001129169.1 Q16586-2A0A0S2Z4P8
SGCANR_135553.2 linkn.457C>A non_coding_transcript_exon_variant Exon 5 of 9

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
SGCAENST00000262018.8 linkc.421C>A p.Arg141Ser missense_variant Exon 5 of 10 1 NM_000023.4 ENSP00000262018.3 Q16586-1

Frequencies

GnomAD3 genomes
AF:
0.000585
AC:
89
AN:
152144
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.000193
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00164
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.000207
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00316
Gnomad NFE
AF:
0.000765
Gnomad OTH
AF:
0.000957
GnomAD2 exomes
AF:
0.000596
AC:
125
AN:
209650
AF XY:
0.000559
show subpopulations
Gnomad AFR exome
AF:
0.0000792
Gnomad AMR exome
AF:
0.000992
Gnomad ASJ exome
AF:
0.000217
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.0000562
Gnomad NFE exome
AF:
0.000857
Gnomad OTH exome
AF:
0.00132
GnomAD4 exome
AF:
0.000837
AC:
1203
AN:
1437470
Hom.:
4
Cov.:
33
AF XY:
0.000810
AC XY:
577
AN XY:
712550
show subpopulations
African (AFR)
AF:
0.000151
AC:
5
AN:
33166
American (AMR)
AF:
0.00115
AC:
47
AN:
41012
Ashkenazi Jewish (ASJ)
AF:
0.000351
AC:
9
AN:
25614
East Asian (EAS)
AF:
0.00
AC:
0
AN:
38756
South Asian (SAS)
AF:
0.000243
AC:
20
AN:
82400
European-Finnish (FIN)
AF:
0.0000195
AC:
1
AN:
51292
Middle Eastern (MID)
AF:
0.00248
AC:
14
AN:
5642
European-Non Finnish (NFE)
AF:
0.000973
AC:
1071
AN:
1100178
Other (OTH)
AF:
0.000606
AC:
36
AN:
59410
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.472
Heterozygous variant carriers
0
66
132
198
264
330
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
Variant carriers
0
42
84
126
168
210
<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:
0.000585
AC:
89
AN:
152262
Hom.:
0
Cov.:
32
AF XY:
0.000578
AC XY:
43
AN XY:
74444
show subpopulations
African (AFR)
AF:
0.000193
AC:
8
AN:
41546
American (AMR)
AF:
0.00163
AC:
25
AN:
15298
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5184
South Asian (SAS)
AF:
0.000207
AC:
1
AN:
4824
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10628
Middle Eastern (MID)
AF:
0.00340
AC:
1
AN:
294
European-Non Finnish (NFE)
AF:
0.000765
AC:
52
AN:
67994
Other (OTH)
AF:
0.000947
AC:
2
AN:
2112
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.495
Heterozygous variant carriers
0
5
10
16
21
26
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:
0.000751
Hom.:
0
Bravo
AF:
0.000888
TwinsUK
AF:
0.000270
AC:
1
ALSPAC
AF:
0.00104
AC:
4
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000698
AC:
6
ExAC
AF:
0.000455
AC:
55

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:9Benign:4
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Autosomal recessive limb-girdle muscular dystrophy type 2D Uncertain:4Benign:2
Dec 29, 2019
Al Jalila Children’s Genomics Center, Al Jalila Childrens Speciality Hospital
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Apr 03, 2020
Natera, Inc.
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Jul 22, 2021
Genome-Nilou Lab
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jan 28, 2020
ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The SGCA c.421C>A; p.Arg141Ser variant (rs35130237) is reported in the literature in several individuals affected with limb-girdle muscular dystrophy or a related sarcoglycanopathy, although a second SGCA variant was not detected in affected individuals (Boito 2003, Trabelsi 2008). The p.Arg141Ser variant is found in the Latino population with an allele frequency of 0.11% (33/31084 alleles) in the Genome Aggregation Database, and it is reported in ClinVar (Variation ID: 197618). The arginine at codon 141 is weakly conserved, and computational analyses (SIFT, PolyPhen-2) predict that this variant is tolerated. However, computational analyses of splicing (Alamut v.2.11) predict that this variant may impact splicing by creating a novel cryptic donor splice site, although RNA analyses would be required to confirm this. Given the lack of clinical and functional data, the significance of the p.Arg141Ser variant is uncertain at this time. References: Boito C et al. Novel sarcoglycan gene mutations in a large cohort of Italian patients. J Med Genet. 2003 May;40(5):e67. Trabelsi M et al. Revised spectrum of mutations in sarcoglycanopathies. Eur J Hum Genet. 2008 Jul;16(7):793-803. -

Jan 29, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Nov 30, 2023
Revvity Omics, Revvity
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not provided Uncertain:5
Sep 17, 2021
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Observed in a patient in the published literature (Boito et al., 2003) with limb-girdle muscular dystrophy who did not have another pathogenic SGCA variant; however, this patient had only mild reduction in alpha-sarcoglycan and normal beta-, delta-, and gamma-sarcoglycan proteins on immunoblot screning on muscle biopsy and Western blot of muscle protein showed a 40% reduction in alpha-sarcoglycan protein; In silico analysis supports that this missense variant does not alter protein structure/function; However, in silico analysis supports this missense variant has a deleterious effect on splicing; This variant is associated with the following publications: (PMID: 18285821, 12746421, 24742800, 31931849) -

Mar 21, 2023
Mayo Clinic Laboratories, Mayo Clinic
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Mar 08, 2018
Eurofins Ntd Llc (ga)
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jan 01, 2020
CeGaT Center for Human Genetics Tuebingen
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jan 10, 2024
Athena Diagnostics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Cardiomyopathy Benign:1
Dec 06, 2017
Center for Advanced Laboratory Medicine, UC San Diego Health, University of California San Diego
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Sarcoglycanopathy Benign:1
Jan 24, 2018
Illumina Laboratory Services, Illumina
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). Publications were found based on this search. The evidence from the literature, in combination with allele frequency data from public databases where available, was sufficient to determine this variant is unlikely to cause disease. Therefore, this variant is classified as likely benign. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.20
BayesDel_addAF
Benign
-0.017
T
BayesDel_noAF
Pathogenic
0.15
CADD
Benign
15
DANN
Uncertain
0.99
DEOGEN2
Uncertain
0.70
.;D;D
Eigen
Benign
-0.42
Eigen_PC
Benign
-0.45
FATHMM_MKL
Benign
0.079
N
LIST_S2
Benign
0.70
T;T;T
M_CAP
Uncertain
0.29
D
MetaRNN
Benign
0.017
T;T;T
MetaSVM
Uncertain
0.25
D
MutationAssessor
Benign
1.8
L;L;.
PhyloP100
0.16
PrimateAI
Benign
0.29
T
PROVEAN
Benign
-0.64
N;N;N
REVEL
Uncertain
0.60
Sift
Benign
0.12
T;T;D
Sift4G
Uncertain
0.057
T;T;D
Polyphen
0.96
D;B;.
Vest4
0.56
MVP
0.94
MPC
0.39
ClinPred
0.016
T
GERP RS
2.3
Varity_R
0.12
gMVP
0.75
Mutation Taster
=10/90
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.020
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: rs35130237; hg19: chr17-48245770; API