13-48476697-G-T

Variant names:

• chr13-48476697-G-T
• rs902298592
• NM_000321.3:c.2521-4G>T

Variant summary

Our verdict is Benign. Variant got -10 ACMG points: 2P and 12B. PM2 BP4_Strong BP6_Very_Strong

The NM_000321.3(RB1):​c.2521-4G>T variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,458,900 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Likely benign (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: RB1 NM_000321.3 splice_region, intron
• Scores: Splicing: ADA: 0.0001668
• Clinical Significance: Likely benign criteria provided, multiple submitters, no conflicts B:4
• Conservation: PhyloP100: -0.510

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]

ACMG classification

Verdict is Benign. Variant got -10 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.71).
• BP6: Variant 13-48476697-G-T is Benign according to our data. Variant chr13-48476697-G-T is described in ClinVar as [Likely_benign]. Clinvar id is 416496.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
RB1	NM_000321.3	c.2521-4G>T		splice_region_variant, intron_variant	Intron 24 of 26	ENST00000267163.6	NP_000312.2
RB1	NM_001407165.1	c.2521-4G>T		splice_region_variant, intron_variant	Intron 24 of 26		NP_001394094.1
RB1	NM_001407168.1	c.-30-4G>T		splice_region_variant, intron_variant	Intron 1 of 3		NP_001394097.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
RB1	ENST00000267163.6	c.2521-4G>T		splice_region_variant, intron_variant	Intron 24 of 26	1	NM_000321.3	ENSP00000267163.4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1458900 Hom.: 0 Cov.: 30 AF XY: 0.00 AC XY: 0 AN XY: 725886

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000224

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 32

ClinVar

Significance: Likely benign

Submissions summary: Benign:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Retinoblastoma Benign:3

May 28, 2019

Mendelics

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Aug 15, 2023

All of Us Research Program, National Institutes of Health

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Oct 12, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Hereditary cancer-predisposing syndrome Benign:1

Nov 15, 2024

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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.71
CADD	Benign	2.0
DANN	Benign	0.74

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.00017
dbscSNV1_RF	Benign	0.0040
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

Other links and lift over

dbSNP: rs902298592; hg19: chr13-49050833;