1-21872727-G-A

Variant summary

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

The NM_005529.7(HSPG2):​c.3922C>T​(p.Arg1308Trp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000249 in 1,608,944 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 34)
Exomes 𝑓: 0.000025 ( 0 hom. )

Consequence

HSPG2
NM_005529.7 missense

Scores

3
9
6

Clinical Significance

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

Conservation

PhyloP100: 1.38

Publications

0 publications found
Variant links:
Genes affected
HSPG2 (HGNC:5273): (heparan sulfate proteoglycan 2) This gene encodes the perlecan protein, which consists of a core protein to which three long chains of glycosaminoglycans (heparan sulfate or chondroitin sulfate) are attached. The perlecan protein is a large multidomain proteoglycan that binds to and cross-links many extracellular matrix components and cell-surface molecules. It has been shown that this protein interacts with laminin, prolargin, collagen type IV, FGFBP1, FBLN2, FGF7 and transthyretin, etc., and it plays essential roles in multiple biological activities. Perlecan is a key component of the vascular extracellular matrix, where it helps to maintain the endothelial barrier function. It is a potent inhibitor of smooth muscle cell proliferation and is thus thought to help maintain vascular homeostasis. It can also promote growth factor (e.g., FGF2) activity and thus stimulate endothelial growth and re-generation. It is a major component of basement membranes, where it is involved in the stabilization of other molecules as well as being involved with glomerular permeability to macromolecules and cell adhesion. Mutations in this gene cause Schwartz-Jampel syndrome type 1, Silverman-Handmaker type of dyssegmental dysplasia, and tardive dyskinesia. Alternative splicing of this gene results in multiple transcript variants. [provided by RefSeq, May 2014]
HSPG2 Gene-Disease associations (from GenCC):
  • Schwartz-Jampel syndrome type 1
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: ClinGen, Labcorp Genetics (formerly Invitae), G2P
  • Silverman-Handmaker type dyssegmental dysplasia
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, G2P, ClinGen, Labcorp Genetics (formerly Invitae)
  • Schwartz-Jampel syndrome
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

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
HSPG2NM_005529.7 linkc.3922C>T p.Arg1308Trp missense_variant Exon 32 of 97 ENST00000374695.8 NP_005520.4

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
HSPG2ENST00000374695.8 linkc.3922C>T p.Arg1308Trp missense_variant Exon 32 of 97 1 NM_005529.7 ENSP00000363827.3
HSPG2ENST00000427897.1 linkn.*132C>T downstream_gene_variant 5 ENSP00000397573.1

Frequencies

GnomAD3 genomes
AF:
0.0000198
AC:
3
AN:
151706
Hom.:
0
Cov.:
34
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:
0.0000442
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000587
AC:
14
AN:
238604
AF XY:
0.0000695
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 FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.000111
Gnomad OTH exome
AF:
0.000173
GnomAD4 exome
AF:
0.0000254
AC:
37
AN:
1457120
Hom.:
0
Cov.:
62
AF XY:
0.0000290
AC XY:
21
AN XY:
724460
show subpopulations
African (AFR)
AF:
0.0000299
AC:
1
AN:
33462
American (AMR)
AF:
0.00
AC:
0
AN:
43718
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25940
East Asian (EAS)
AF:
0.0000253
AC:
1
AN:
39492
South Asian (SAS)
AF:
0.0000118
AC:
1
AN:
85100
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
52936
Middle Eastern (MID)
AF:
0.000351
AC:
2
AN:
5692
European-Non Finnish (NFE)
AF:
0.0000279
AC:
31
AN:
1110634
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60146
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.437
Heterozygous variant carriers
0
3
7
10
14
17
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:
0.0000198
AC:
3
AN:
151824
Hom.:
0
Cov.:
34
AF XY:
0.0000135
AC XY:
1
AN XY:
74256
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41410
American (AMR)
AF:
0.00
AC:
0
AN:
15272
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5086
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4810
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10614
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
292
European-Non Finnish (NFE)
AF:
0.0000442
AC:
3
AN:
67852
Other (OTH)
AF:
0.00
AC:
0
AN:
2106
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.492
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.0000329
Hom.:
0
Bravo
AF:
0.0000189
ExAC
AF:
0.0000495
AC:
6

ClinVar

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

Submissions by phenotype

not specified Uncertain:1
Dec 30, 2016
Athena Diagnostics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Inborn genetic diseases Uncertain:1
Jul 10, 2024
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.3922C>T (p.R1308W) alteration is located in exon 31 (coding exon 31) of the HSPG2 gene. This alteration results from a C to T substitution at nucleotide position 3922, causing the arginine (R) at amino acid position 1308 to be replaced by a tryptophan (W). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear.

not provided Uncertain:1
Aug 10, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces arginine, which is basic and polar, with tryptophan, which is neutral and slightly polar, at codon 1308 of the HSPG2 protein (p.Arg1308Trp). This variant is present in population databases (rs758559575, gnomAD 0.01%). This variant has not been reported in the literature in individuals affected with HSPG2-related conditions. ClinVar contains an entry for this variant (Variation ID: 447550). An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be disruptive. 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
0.15
BayesDel_addAF
Benign
-0.12
T
BayesDel_noAF
Benign
-0.19
CADD
Pathogenic
27
DANN
Pathogenic
1.0
DEOGEN2
Uncertain
0.55
D
Eigen
Uncertain
0.44
Eigen_PC
Uncertain
0.32
FATHMM_MKL
Uncertain
0.83
D
LIST_S2
Benign
0.79
T
M_CAP
Uncertain
0.15
D
MetaRNN
Uncertain
0.70
D
MetaSVM
Benign
-0.28
T
MutationAssessor
Pathogenic
3.0
M
PhyloP100
1.4
PrimateAI
Benign
0.35
T
PROVEAN
Pathogenic
-6.2
D
REVEL
Uncertain
0.36
Sift
Uncertain
0.011
D
Sift4G
Uncertain
0.0020
D
Vest4
0.45
ClinPred
0.73
D
GERP RS
1.9
PromoterAI
0.0091
Neutral
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.14
gMVP
0.54
Mutation Taster
=80/20
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: rs758559575; hg19: chr1-22199220; COSMIC: COSV101021049; COSMIC: COSV101021049; API