chr18-23001699-G-T

Variant names:

• chr18-23001699-G-T
• rs774631370
• NM_002894.3:c.2257G>T

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PVS1 PM2

The NM_002894.3(RBBP8):​c.2257G>T​(p.Glu753*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000124 in 1,613,870 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: RBBP8 NM_002894.3 stop_gained
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 1.87
• Publications: 3 publications found

Genes affected

RBBP8 (HGNC:9891): (RB binding protein 8, endonuclease) The protein encoded by this gene is a ubiquitously expressed nuclear protein. It is found among several proteins that bind directly to retinoblastoma protein, which regulates cell proliferation. This protein complexes with transcriptional co-repressor CTBP. It is also associated with BRCA1 and is thought to modulate the functions of BRCA1 in transcriptional regulation, DNA repair, and/or cell cycle checkpoint control. It is suggested that this gene may itself be a tumor suppressor acting in the same pathway as BRCA1. Three transcript variants encoding two different isoforms have been found for this gene. More transcript variants exist, but their full-length natures have not been determined. [provided by RefSeq, Jul 2008]

RBBP8 Gene-Disease associations (from GenCC):

• Jawad syndrome

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, Labcorp Genetics (formerly Invitae), G2P
• Seckel syndrome 2

  Inheritance: AR Classification: MODERATE Submitted by: Ambry Genetics
• Seckel syndrome

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 10 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_002894.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	RBBP8	NM_002894.3	MANE Select	c.2257G>T	p.Glu753*	stop_gained	Exon 15 of 19	NP_002885.1	Q99708-1
	RBBP8	NM_203291.2		c.2257G>T	p.Glu753*	stop_gained	Exon 15 of 19	NP_976036.1	Q99708-1
	RBBP8	NM_203292.2		c.2257G>T	p.Glu753*	stop_gained	Exon 15 of 18	NP_976037.1	Q99708-3

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	RBBP8	ENST00000327155.10	TSL:1 MANE Select	c.2257G>T	p.Glu753*	stop_gained	Exon 15 of 19	ENSP00000323050.5	Q99708-1
	RBBP8	ENST00000360790.9	TSL:1	c.2272G>T	p.Glu758*	stop_gained	Exon 15 of 19	ENSP00000354024.5	I6L8A6
	RBBP8	ENST00000399722.6	TSL:1	c.2257G>T	p.Glu753*	stop_gained	Exon 15 of 19	ENSP00000382628.2	Q99708-1

Frequencies

GnomAD3 genomes AF: 0.00000658 AC: 1 AN: 152056 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000147

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461814 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 727208

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

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26130

East Asian (EAS) AF: 0.00 AC: 0 AN: 39674

South Asian (SAS) AF: 0.0000116 AC: 1 AN: 86256

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53420

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5766

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111980

Other (OTH) AF: 0.00 AC: 0 AN: 60388

GnomAD4 genome AF: 0.00000658 AC: 1 AN: 152056 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74280

African (AFR) AF: 0.00 AC: 0 AN: 41396

American (AMR) AF: 0.00 AC: 0 AN: 15266

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3466

East Asian (EAS) AF: 0.00 AC: 0 AN: 5188

South Asian (SAS) AF: 0.00 AC: 0 AN: 4816

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10604

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.0000147 AC: 1 AN: 68008

Other (OTH) AF: 0.00 AC: 0 AN: 2086

Alfa AF: 0.00 Hom.: 0

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.29
CADD	Pathogenic	36
DANN	Uncertain	0.99
Eigen	Uncertain	0.57
Eigen_PC	Uncertain	0.31
FATHMM_MKL	Uncertain	0.84	D
PhyloP100		1.9
Vest4		0.80
GERP RS		2.8

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: rs774631370; hg19: chr18-20581662;