dbSNP rs752897010: RB1:p.Ala885Thr (chr13-48476833-G-A) – ACMG Classification: Likely_benign (-3 pts)

Variant summary

Our verdict is Likely benign. Variant got -3 ACMG points: 2P and 5B. PM1BP4BS2

The NM_000321.3(RB1):c.2653G>A(p.Ala885Thr) variant causes a missense change. The variant allele was found at a frequency of 0.0000151 in 1,461,260 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: not found (cov: 32)

Exomes 𝑓: 0.000015 ( 1 hom. )

Consequence

RB1
NM_000321.3 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 6.01

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 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -3 ACMG points.

PM1

In a region_of_interest Domain C; mediates interaction with E4F1 (size 157) in uniprot entity RB_HUMAN there are 8 pathogenic changes around while only 0 benign (100%) in NM_000321.3

BP4

Computational evidence support a benign effect (MetaRNN=0.29921538).

BS2

High AC in GnomAdExome4 at 22 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
RB1	NM_000321.3 link	c.2653G>A	p.Ala885Thr	missense_variant	Exon 25 of 27	ENST00000267163.6	NP_000312.2	P06400A0A024RDV3
RB1	NM_001407165.1 link	c.2653G>A	p.Ala885Thr	missense_variant	Exon 25 of 27		NP_001394094.1
RB1	NM_001407168.1 link	c.103G>A	p.Ala35Thr	missense_variant	Exon 2 of 4		NP_001394097.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
RB1	ENST00000267163.6 link	c.2653G>A	p.Ala885Thr	missense_variant	Exon 25 of 27	1	NM_000321.3	ENSP00000267163.4		P06400

Frequencies

GnomAD3 genomes

Cov.:

GnomAD3 exomes

AF:

0.0000119

AC:

AN:

251306

Hom.:

AF XY:

0.0000221

AC XY:

AN XY:

135808

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 SAS exome

AF:

0.0000980

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000151

AC:

AN:

1461260

Hom.:

Cov.:

AF XY:

0.0000234

AC XY:

AN XY:

726950

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.000209

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00

Gnomad4 OTH exome

AF:

0.0000663

GnomAD4 genome

Cov.:

Bravo

AF:

0.00000378

ExAC

AF:

0.0000165

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Retinoblastoma

Uncertain:1

Jul 21, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces alanine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 885 of the RB1 protein (p.Ala885Thr). This variant is present in population databases (rs752897010, gnomAD 0.01%). This variant has not been reported in the literature in individuals affected with RB1-related conditions. ClinVar contains an entry for this variant (Variation ID: 458155). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) has been performed at Invitae for this missense variant, however the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on RB1 protein function. 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. -

Hereditary cancer-predisposing syndrome

Uncertain:1

Sep 08, 2020

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.A885T variant (also known as c.2653G>A), located in coding exon 25 of the RB1 gene, results from a G to A substitution at nucleotide position 2653. The alanine at codon 885 is replaced by threonine, an amino acid with similar properties. This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.096

BayesDel_addAF

Benign

-0.13

BayesDel_noAF

Benign

-0.23

CADD

Benign

DANN

Uncertain

1.0

DEOGEN2

Benign

0.39

T;.

Eigen

Uncertain

0.20

Eigen_PC

Uncertain

0.29

FATHMM_MKL

Uncertain

0.90

LIST_S2

Benign

0.82

T;T

M_CAP

Benign

0.060

MetaRNN

Benign

0.30

T;T

MetaSVM

Uncertain

-0.27

MutationAssessor

Benign

1.4

L;.

PrimateAI

Uncertain

0.60

PROVEAN

Benign

-0.96

N;.

REVEL

Uncertain

0.32

Sift

Benign

0.074

T;.

Sift4G

Benign

0.096

T;.

Polyphen

0.63

P;.

Vest4

0.41

MutPred

0.35

Gain of phosphorylation at A885 (P = 0.0124);Gain of phosphorylation at A885 (P = 0.0124);

MVP

0.79

MPC

0.81

ClinPred

0.71

GERP RS

4.1

Varity_R

0.15

gMVP

0.31

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.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over