rs367576664

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PVS1PP5_Moderate

The NM_001563.4(IMPG1):​c.1519C>T​(p.Arg507*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000285 in 1,613,732 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★). Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: 𝑓 0.000046 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000027 ( 1 hom. )

Consequence

IMPG1
NM_001563.4 stop_gained

Scores

1
1
5

Clinical Significance

Pathogenic criteria provided, single submitter P:2U:1

Conservation

PhyloP100: -1.14
Variant links:
Genes affected
IMPG1 (HGNC:6055): (interphotoreceptor matrix proteoglycan 1) This gene encodes a protein that is a major component of the retinal interphotoreceptor matrix. The encoded protein is a proteoglycan that is thought to play a role in maintaining viability of photoreceptor cells and in adhesion of the neural retina to the retinal pigment epithelium. Alternate splicing results in multiple transcript variants. [provided by RefSeq, Sep 2013]

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 10 ACMG points.

PVS1
Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
PP5
Variant 6-75950867-G-A is Pathogenic according to our data. Variant chr6-75950867-G-A is described in ClinVar as [Pathogenic]. Clinvar id is 162135.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr6-75950867-G-A is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
IMPG1NM_001563.4 linkc.1519C>T p.Arg507* stop_gained Exon 13 of 17 ENST00000369950.8 NP_001554.2 Q17R60-1
IMPG1NM_001282368.2 linkc.1285C>T p.Arg429* stop_gained Exon 12 of 16 NP_001269297.1 Q17R60A0A087WYL3

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
IMPG1ENST00000369950.8 linkc.1519C>T p.Arg507* stop_gained Exon 13 of 17 1 NM_001563.4 ENSP00000358966.3 Q17R60-1
IMPG1ENST00000611179.4 linkc.1285C>T p.Arg429* stop_gained Exon 12 of 16 5 ENSP00000481913.1 A0A087WYL3

Frequencies

GnomAD3 genomes
AF:
0.0000460
AC:
7
AN:
152174
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000483
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
GnomAD2 exomes
AF:
0.0000120
AC:
3
AN:
250894
AF XY:
0.0000147
show subpopulations
Gnomad AFR exome
AF:
0.0000616
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:
0.00000881
Gnomad OTH exome
AF:
0.000164
GnomAD4 exome
AF:
0.0000267
AC:
39
AN:
1461558
Hom.:
1
Cov.:
33
AF XY:
0.0000275
AC XY:
20
AN XY:
727078
show subpopulations
Gnomad4 AFR exome
AF:
0.0000299
AC:
1
AN:
33464
Gnomad4 AMR exome
AF:
0.00
AC:
0
AN:
44652
Gnomad4 ASJ exome
AF:
0.00
AC:
0
AN:
26128
Gnomad4 EAS exome
AF:
0.0000252
AC:
1
AN:
39690
Gnomad4 SAS exome
AF:
0.0000348
AC:
3
AN:
86244
Gnomad4 FIN exome
AF:
0.0000375
AC:
2
AN:
53360
Gnomad4 NFE exome
AF:
0.0000279
AC:
31
AN:
1111876
Gnomad4 Remaining exome
AF:
0.0000166
AC:
1
AN:
60384
Heterozygous variant carriers
0
2
4
7
9
11
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
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:
0.0000460
AC:
7
AN:
152174
Hom.:
0
Cov.:
32
AF XY:
0.0000269
AC XY:
2
AN XY:
74332
show subpopulations
Gnomad4 AFR
AF:
0.0000483
AC:
0.0000482672
AN:
0.0000482672
Gnomad4 AMR
AF:
0.00
AC:
0
AN:
0
Gnomad4 ASJ
AF:
0.00
AC:
0
AN:
0
Gnomad4 EAS
AF:
0.00
AC:
0
AN:
0
Gnomad4 SAS
AF:
0.00
AC:
0
AN:
0
Gnomad4 FIN
AF:
0.00
AC:
0
AN:
0
Gnomad4 NFE
AF:
0.0000735
AC:
0.000073484
AN:
0.000073484
Gnomad4 OTH
AF:
0.00
AC:
0
AN:
0
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
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:
0.0000538
Hom.:
0
Bravo
AF:
0.0000378
ESP6500AA
AF:
0.000227
AC:
1
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.00000824
AC:
1

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:2Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Vitelliform macular dystrophy 4 Pathogenic:1
Sep 05, 2013
OMIM
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:literature only

- -

not provided Pathogenic:1
Aug 10, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

For these reasons, this variant has been classified as Pathogenic. ClinVar contains an entry for this variant (Variation ID: 162135). This premature translational stop signal has been observed in individual(s) with autosomal recessive macular dystrophy (PMID: 23993198). It has also been observed to segregate with disease in related individuals. This variant is present in population databases (rs367576664, gnomAD 0.004%). This sequence change creates a premature translational stop signal (p.Arg507*) in the IMPG1 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in IMPG1 are known to be pathogenic (PMID: 23993198). -

IMPG1-related disorder Uncertain:1
Sep 09, 2024
PreventionGenetics, part of Exact Sciences
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

The IMPG1 c.1519C>T variant is predicted to result in premature protein termination (p.Arg507*). This variant has been reported in the compound heterozygous state in two siblings with vitelliform macular dystrophy (Manes et al. 2013. PubMed ID: 23993198). This variant is reported in 0.0040% of alleles in individuals of African descent in gnomAD. Nonsense variants in IMPG1 are not yet a fully established mechanism of disease. Although we suspect that this variant may be pathogenic, at this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.50
D
BayesDel_noAF
Uncertain
0.070
CADD
Pathogenic
29
DANN
Benign
0.97
Eigen
Benign
-0.48
Eigen_PC
Benign
-0.86
FATHMM_MKL
Benign
0.080
N
Vest4
0.18
GERP RS
-2.5
Mutation Taster
=9/191
disease causing (fs/PTC)

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: rs367576664; hg19: chr6-76660584; API