rs374157786

Variant summary

Our verdict is Likely benign. The variant received -4 ACMG points: 1P and 5B. PP3BP6BS2

The NM_000321.3(RB1):​c.2518G>A​(p.Gly840Arg) variant causes a missense, splice region change. The variant allele was found at a frequency of 0.0000339 in 1,561,456 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 2/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Uncertain significance in ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G840W) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000035 ( 0 hom. )

Consequence

RB1
NM_000321.3 missense, splice_region

Scores

7
7
4
Splicing: ADA: 0.9498
1
1

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:5B:2

Conservation

PhyloP100: 6.97

Publications

2 publications found
Variant links:
Genes affected
RB1 (HGNC:9884): (RB transcriptional corepressor 1) The protein encoded by this gene is a negative regulator of the cell cycle and was the first tumor suppressor gene found. The encoded protein also stabilizes constitutive heterochromatin to maintain the overall chromatin structure. The active, hypophosphorylated form of the protein binds transcription factor E2F1. Defects in this gene are a cause of childhood cancer retinoblastoma (RB), bladder cancer, and osteogenic sarcoma. [provided by RefSeq, Jul 2008]
RB1 Gene-Disease associations (from GenCC):
  • hereditary retinoblastoma
    Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Orphanet, G2P, Ambry Genetics
  • retinoblastoma
    Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
  • melanoma
    Inheritance: AD Classification: MODERATE Submitted by: Ambry Genetics

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -4 ACMG points.

PP3
MetaRNN computational evidence supports a deleterious effect, 0.797
BP6
Variant 13-48473388-G-A is Benign according to our data. Variant chr13-48473388-G-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 237670.
BS2
High AC in GnomAdExome4 at 50 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
RB1NM_000321.3 linkc.2518G>A p.Gly840Arg missense_variant, splice_region_variant Exon 24 of 27 ENST00000267163.6 NP_000312.2
RB1NM_001407165.1 linkc.2518G>A p.Gly840Arg missense_variant, splice_region_variant Exon 24 of 27 NP_001394094.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
RB1ENST00000267163.6 linkc.2518G>A p.Gly840Arg missense_variant, splice_region_variant Exon 24 of 27 1 NM_000321.3 ENSP00000267163.4

Frequencies

GnomAD3 genomes
AF:
0.0000197
AC:
3
AN:
151954
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:
0.0000441
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000240
AC:
6
AN:
250396
AF XY:
0.0000369
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000290
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000441
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000355
AC:
50
AN:
1409502
Hom.:
0
Cov.:
28
AF XY:
0.0000412
AC XY:
29
AN XY:
703954
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
32188
American (AMR)
AF:
0.00
AC:
0
AN:
44564
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25768
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39268
South Asian (SAS)
AF:
0.0000235
AC:
2
AN:
85142
European-Finnish (FIN)
AF:
0.0000190
AC:
1
AN:
52740
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5052
European-Non Finnish (NFE)
AF:
0.0000403
AC:
43
AN:
1066186
Other (OTH)
AF:
0.0000683
AC:
4
AN:
58594
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.432
Heterozygous variant carriers
0
3
5
8
10
13
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
4
8
12
16
20
<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:
0.0000197
AC:
3
AN:
151954
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74234
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41334
American (AMR)
AF:
0.00
AC:
0
AN:
15258
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3466
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5198
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4808
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10594
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000441
AC:
3
AN:
67982
Other (OTH)
AF:
0.00
AC:
0
AN:
2086
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.542
Heterozygous variant carriers
0
0
1
1
2
2
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:
0.0000434
Hom.:
0
Bravo
AF:
0.0000151
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.00000824
AC:
1
EpiCase
AF:
0.0000546
EpiControl
AF:
0.00

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:5Benign:2
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Retinoblastoma Uncertain:3Benign:1
Apr 07, 2024
St. Jude Molecular Pathology, St. Jude Children's Research Hospital
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The RB1 c.2518G>A (p.Gly840Arg) missense change has a maximum subpopulation frequency of 0.004% in gnomAD v2.1.1 (https://gnomad.broadinstitute.org). The in silico tool REVEL predicts a deleterious effect on protein function, but to our knowledge this prediction has not been confirmed by functional studies. To our knowledge, this variant has not been reported in individuals with retinoblastoma. In summary, the evidence currently available is insufficient to determine the clinical significance of this variant. It has therefore been classified as of uncertain significance.

Oct 10, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Jul 29, 2024
All of Us Research Program, National Institutes of Health
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This missense variant replaces glycine with arginine at codon 840 of the RB1 protein. Computational prediction suggests that this variant may have deleterious impact on protein structure and function (internally defined REVEL score threshold >= 0.7, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has not been reported in individuals affected with RB1-related disorders in the literature. This variant has been identified in 6/250396 chromosomes in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance.

Jul 02, 2018
Mendelics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Hereditary cancer-predisposing syndrome Uncertain:1Benign:1
Sep 02, 2021
Ambry Genetics
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity.

Nov 15, 2021
Sema4, Sema4
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:curation

RB1-related disorder Uncertain:1
Oct 26, 2022
PreventionGenetics, part of Exact Sciences
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The RB1 c.2518G>A variant is predicted to result in the amino acid substitution p.Gly840Arg. To our knowledge, this variant has not been reported as a germline variant in an individual with RB1-related disease. It has been reported as a somatic variant in an individual with metastatic breast cancer; however, this individual also had a pathogenic somatic variant in BRCA2 (Schwartzberg and Kiedrowski. 2021. PubMed ID: 33868464). This variant is reported in 0.0044% of alleles in individuals of European (Non-Finnish) descent in gnomAD (http://gnomad.broadinstitute.org/variant/13-49047524-G-A) and has conflicting interpretations in ClinVar of likely benign and uncertain (https://www.ncbi.nlm.nih.gov/clinvar/variation/237670/). 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
AlphaMissense
Pathogenic
0.77
BayesDel_addAF
Pathogenic
0.29
D
BayesDel_noAF
Pathogenic
0.31
CADD
Pathogenic
33
DANN
Pathogenic
1.0
DEOGEN2
Uncertain
0.47
T;.
Eigen
Uncertain
0.56
Eigen_PC
Uncertain
0.63
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.90
D;D
M_CAP
Benign
0.079
D
MetaRNN
Pathogenic
0.80
D;D
MetaSVM
Uncertain
0.17
D
MutationAssessor
Benign
1.4
L;.
PhyloP100
7.0
PrimateAI
Uncertain
0.79
T
PROVEAN
Benign
-1.5
N;.
REVEL
Pathogenic
0.74
Sift
Benign
0.10
T;.
Sift4G
Uncertain
0.060
T;.
Vest4
0.90
ClinPred
0.76
D
GERP RS
5.7
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.50
gMVP
0.75
Mutation Taster
=18/82
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Benign
0.95
dbscSNV1_RF
Pathogenic
0.80
SpliceAI score (max)
0.15
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: rs374157786; hg19: chr13-49047524; API