13-48465239-G-C

Variant names:

• chr13-48465239-G-C
• rs748094394
• NM_000321.3:c.2360G>C

Variant summary

Our verdict is Likely benign. The variant received -1 ACMG points: 0P and 1B. BS2_Supporting

The NM_000321.3(RB1):​c.2360G>C​(p.Arg787Pro) variant causes a missense change. The variant allele was found at a frequency of 0.0000041 in 1,461,740 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R787Q) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 29)
  • Exomes 𝑓: 0.0000041 (0 hom.)
• Consequence: RB1 NM_000321.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 6.28
• Publications: 14 publications found

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

ACMG classification

Our verdict: Likely_benign. The variant received -1 ACMG points.

• BS2: High AC in GnomAdExome4 at 6 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
RB1	NM_000321.3	c.2360G>C	p.Arg787Pro	missense_variant	Exon 23 of 27	ENST00000267163.6	NP_000312.2
RB1	NM_001407165.1	c.2360G>C	p.Arg787Pro	missense_variant	Exon 23 of 27		NP_001394094.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
RB1	ENST00000267163.6	c.2360G>C	p.Arg787Pro	missense_variant	Exon 23 of 27	1	NM_000321.3	ENSP00000267163.4

Frequencies

GnomAD3 genomes Cov.: 29

GnomAD2 exomes AF: 0.00000398 AC: 1 AN: 251418 AF XY: 0.00000736

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 FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000879

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000410 AC: 6 AN: 1461740 Hom.: 0 Cov.: 34 AF XY: 0.00000413 AC XY: 3 AN XY: 727188

African (AFR) AF: 0.00 AC: 0 AN: 33476

American (AMR) AF: 0.00 AC: 0 AN: 44722

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26132

East Asian (EAS) AF: 0.00 AC: 0 AN: 39680

South Asian (SAS) AF: 0.00 AC: 0 AN: 86254

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53412

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00000540 AC: 6 AN: 1111906

Other (OTH) AF: 0.00 AC: 0 AN: 60390

GnomAD4 genome Cov.: 29

ExAC AF: 0.00000824 AC: 1

EpiCase AF: 0.00

EpiControl AF: 0.0000593

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:1

May 02, 2025

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.R787P variant (also known as c.2360G>C), located in coding exon 23 of the RB1 gene, results from a G to C substitution at nucleotide position 2360. The arginine at codon 787 is replaced by proline, an amino acid with dissimilar properties. This amino acid position is conserved. In addition, the in silico prediction for this alteration is inconclusive. 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	Uncertain	0.34
BayesDel_addAF	Uncertain	0.12	D
BayesDel_noAF	Uncertain	-0.070
CADD	Uncertain	24
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.62	D;.
Eigen	Uncertain	0.52
Eigen_PC	Uncertain	0.61
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.94	D;D
M_CAP	Benign	0.073	D
MetaRNN	Uncertain	0.57	D;D
MetaSVM	Uncertain	-0.075	T
MutationAssessor	Benign	1.0	L;.
PhyloP100		6.3
PrimateAI	Uncertain	0.64	T
PROVEAN	Benign	-2.1	N;.
REVEL	Uncertain	0.58
Sift	Uncertain	0.020	D;.
Sift4G	Uncertain	0.037	D;.
Vest4		0.51
ClinPred		0.75	D
GERP RS		5.9
Varity_R		0.90
gMVP		0.69
Mutation Taster		=42/58	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs748094394; hg19: chr13-49039375;