13-48476843-G-T

Position:

• chr13-48476843-G-T

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM1 PM2

The NM_000321.3(RB1):​c.2663G>T​(p.Ser888Ile) variant causes a missense, splice region change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. 3/3 splice prediction tools predicting alterations to normal splicing. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency: Genomes: not found (cov: 32)
• Consequence: RB1 NM_000321.3 missense, splice_region
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 9.04

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 (HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 4 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
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
RB1	NM_000321.3	c.2663G>T	p.Ser888Ile	missense_variant, splice_region_variant	25/27	ENST00000267163.6	NP_000312.2
RB1	NM_001407165.1	c.2663G>T	p.Ser888Ile	missense_variant, splice_region_variant	25/27		NP_001394094.1
RB1	NM_001407168.1	c.113G>T	p.Ser38Ile	missense_variant, splice_region_variant	2/4		NP_001394097.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
RB1	ENST00000267163.6	c.2663G>T	p.Ser888Ile	missense_variant, splice_region_variant	25/27	1	NM_000321.3	ENSP00000267163.4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.37
BayesDel_addAF	Uncertain	0.10	D
BayesDel_noAF	Benign	-0.090
CADD	Pathogenic	34
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.48	T;.
Eigen	Pathogenic	0.81
Eigen_PC	Pathogenic	0.84
FATHMM_MKL	Uncertain	0.95	D
LIST_S2	Uncertain	0.88	D;D
M_CAP	Uncertain	0.14	D
MetaRNN	Uncertain	0.52	D;D
MetaSVM	Uncertain	0.45	D
MutationAssessor	Benign	1.1	L;.
PrimateAI	Uncertain	0.57	T
PROVEAN	Benign	-1.9	N;.
REVEL	Uncertain	0.64
Sift	Uncertain	0.0020	D;.
Sift4G	Uncertain	0.0030	D;.
Polyphen		1.0	D;.
Vest4		0.52
MutPred		0.46		Gain of catalytic residue at L891 (P = 4e-04);Gain of catalytic residue at L891 (P = 4e-04);
MVP		0.73
MPC		1.4
ClinPred		0.94	D
GERP RS		5.8
Varity_R		0.42
gMVP		0.42

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	1.0
SpliceAI score (max)		0.89		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.89		Position offset: 0

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

Publications

No publications associated with this variant yet.

Other links and lift over

hg19: chr13-49050979; COSMIC: COSV57311142;