rs1060503086

Variant summary

Our verdict is Likely benign. The variant received -6 ACMG points: 0P and 6B. BP4_StrongBP6BS2_Supporting

The NM_000321.3(RB1):​c.898A>C​(p.Met300Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000446 in 1,569,126 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 16/22 in silico tools predict a benign outcome for this variant. 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. M300T) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000035 ( 0 hom. )

Consequence

RB1
NM_000321.3 missense

Scores

1
18

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:3B:2

Conservation

PhyloP100: 1.56

Publications

0 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 -6 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.0569942).
BP6
Variant 13-48364930-A-C is Benign according to our data. Variant chr13-48364930-A-C is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 410938.
BS2
High AC in GnomAdExome4 at 5 AD gene. Variant has AC lower than other variant known as pathogenic in the gene, so the strength is limited to Supporting.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
RB1NM_000321.3 linkc.898A>C p.Met300Leu missense_variant Exon 9 of 27 ENST00000267163.6 NP_000312.2 P06400A0A024RDV3
RB1NM_001407165.1 linkc.898A>C p.Met300Leu missense_variant Exon 9 of 27 NP_001394094.1
RB1NM_001407166.1 linkc.898A>C p.Met300Leu missense_variant Exon 9 of 17 NP_001394095.1
LOC112268118XR_002957522.2 linkn.168T>G non_coding_transcript_exon_variant Exon 3 of 3

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
RB1ENST00000267163.6 linkc.898A>C p.Met300Leu missense_variant Exon 9 of 27 1 NM_000321.3 ENSP00000267163.4 P06400

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152184
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:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000516
AC:
1
AN:
193920
AF XY:
0.00
show subpopulations
Gnomad AFR exome
AF:
0.0000906
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:
0.00000353
AC:
5
AN:
1416942
Hom.:
0
Cov.:
30
AF XY:
0.00000713
AC XY:
5
AN XY:
701190
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
31892
American (AMR)
AF:
0.00
AC:
0
AN:
41470
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25350
East Asian (EAS)
AF:
0.00
AC:
0
AN:
37466
South Asian (SAS)
AF:
0.00
AC:
0
AN:
81512
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
50422
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5536
European-Non Finnish (NFE)
AF:
0.00000461
AC:
5
AN:
1085026
Other (OTH)
AF:
0.00
AC:
0
AN:
58268
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.465
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:
0.0000131
AC:
2
AN:
152184
Hom.:
0
Cov.:
32
AF XY:
0.0000134
AC XY:
1
AN XY:
74350
show subpopulations
African (AFR)
AF:
0.0000483
AC:
2
AN:
41446
American (AMR)
AF:
0.00
AC:
0
AN:
15288
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3462
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5202
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4824
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10612
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68028
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.550
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

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:3Benign:2
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Retinoblastoma Uncertain:2Benign:1
Dec 13, 2023
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 methionine with leucine at codon 300 of the RB1 protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, 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 1/193920 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. -

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

- -

Jul 18, 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.898A>C (p.Met300Leu) missense change has a maximum subpopulation frequency of 0.009% in gnomAD v2.1.1 (https://gnomad.broadinstitute.org). The in silico tool REVEL predicts a benign 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. -

not provided Uncertain:1
Sep 01, 2024
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis indicates that this missense variant does not alter protein structure/function; Has not been previously published as pathogenic or benign to our knowledge; This variant is associated with the following publications: (PMID: 23516486) -

Hereditary cancer-predisposing syndrome Benign:1
Apr 25, 2024
Ambry Genetics
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This alteration is classified as 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. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.080
BayesDel_addAF
Benign
-0.19
T
BayesDel_noAF
Benign
-0.31
CADD
Benign
16
DANN
Benign
0.76
DEOGEN2
Benign
0.28
T;.
Eigen
Benign
-0.64
Eigen_PC
Benign
-0.31
FATHMM_MKL
Benign
0.61
D
LIST_S2
Benign
0.74
T;T
M_CAP
Benign
0.013
T
MetaRNN
Benign
0.057
T;T
MetaSVM
Benign
-0.74
T
MutationAssessor
Benign
-2.2
N;.
PhyloP100
1.6
PrimateAI
Uncertain
0.56
T
PROVEAN
Benign
0.48
N;.
REVEL
Benign
0.17
Sift
Benign
1.0
T;.
Sift4G
Benign
1.0
T;.
Polyphen
0.0
B;.
Vest4
0.26
MutPred
0.44
Gain of catalytic residue at S302 (P = 5e-04);Gain of catalytic residue at S302 (P = 5e-04);
MVP
0.59
MPC
0.41
ClinPred
0.072
T
GERP RS
4.3
Varity_R
0.27
gMVP
0.54
Mutation Taster
=93/7
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: rs1060503086; hg19: chr13-48939066; API