NM_000321.3:c.1399C>G

Variant names:

• chr13-48380062-C-G
• rs398123331
• NM_000321.3:c.1399C>G

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM1 PM2 PP3_Moderate

The NM_000321.3(RB1):​c.1399C>G​(p.Arg467Gly) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency: Genomes: not found (cov: 29)
• Consequence: RB1 NM_000321.3 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: 3.32

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]

LOC112268118 (HGNC:):

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PM1: In a helix (size 29) in uniprot entity RB_HUMAN there are 5 pathogenic changes around while only 0 benign (100%) in NM_000321.3
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.928

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
RB1	NM_000321.3	c.1399C>G	p.Arg467Gly	missense_variant	Exon 15 of 27	ENST00000267163.6	NP_000312.2
RB1	NM_001407165.1	c.1399C>G	p.Arg467Gly	missense_variant	Exon 15 of 27		NP_001394094.1
RB1	NM_001407166.1	c.1399C>G	p.Arg467Gly	missense_variant	Exon 15 of 17		NP_001394095.1
LOC112268118	XR_002957522.2	n.-188G>C		upstream_gene_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
RB1	ENST00000267163.6	c.1399C>G	p.Arg467Gly	missense_variant	Exon 15 of 27	1	NM_000321.3	ENSP00000267163.4
RB1	ENST00000650461.1	c.1399C>G	p.Arg467Gly	missense_variant	Exon 15 of 27			ENSP00000497193.1

Frequencies

GnomAD3 genomes Cov.: 29

GnomAD4 exome Cov.: 22

GnomAD4 genome Cov.: 29

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Retinoblastoma Uncertain:2

Jul 19, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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. This sequence change replaces arginine, which is basic and polar, with glycine, which is neutral and non-polar, at codon 467 of the RB1 protein (p.Arg467Gly). This variant is not present in population databases (gnomAD no frequency). 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: 584871). Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be disruptive. -

Jul 02, 2018

Mendelics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Hereditary cancer-predisposing syndrome Uncertain:1

Sep 19, 2024

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.R467G variant (also known as c.1399C>G), located in coding exon 15 of the RB1 gene, results from a C to G substitution at nucleotide position 1399. The arginine at codon 467 is replaced by glycine, an amino acid with dissimilar properties. This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Based on the available evidence, the clinical significance of this variant remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.40	D
BayesDel_noAF	Pathogenic	0.34
CADD	Uncertain	24
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.90	D;.
Eigen	Uncertain	0.53
Eigen_PC	Uncertain	0.48
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.94	D;D
M_CAP	Pathogenic	0.52	D
MetaRNN	Pathogenic	0.93	D;D
MetaSVM	Pathogenic	0.86	D
MutationAssessor	Pathogenic	2.9	M;.
PrimateAI	Uncertain	0.64	T
PROVEAN	Pathogenic	-5.5	D;.
REVEL	Pathogenic	0.87
Sift	Pathogenic	0.0	D;.
Sift4G	Pathogenic	0.0	D;.
Polyphen		1.0	D;.
Vest4		0.82
MutPred		0.78		Loss of helix (P = 0.0237);Loss of helix (P = 0.0237);
MVP		0.94
MPC		1.5
ClinPred		1.0	D
GERP RS		4.7
Varity_R		0.99
gMVP		0.77

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.030		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

Other links and lift over

dbSNP: rs398123331; hg19: chr13-48954198;