rs1555493707

Variant names:

• chr16-57959886-A-T
• rs1555493707
• NM_001297.5:c.761+2T>A

Variant summary

Our verdict is Pathogenic. The variant received 11 ACMG points: 11P and 0B. PVS1 PM2 PP5

The NM_001297.5(CNGB1):​c.761+2T>A variant causes a splice donor, intron 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. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (no stars).

• Frequency: Genomes: not found (cov: 32)
• Consequence: CNGB1 NM_001297.5 splice_donor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Likely pathogenic no assertion criteria provided P:1
• Conservation: PhyloP100: 3.52
• Publications: 3 publications found

Genes affected

CNGB1 (HGNC:2151): (cyclic nucleotide gated channel subunit beta 1) In humans, the rod photoreceptor cGMP-gated cation channel helps regulate ion flow into the rod photoreceptor outer segment in response to light-induced alteration of the levels of intracellular cGMP. This channel consists of two subunits, alpha and beta, with the protein encoded by this gene representing the beta subunit. Defects in this gene are a cause of cause of retinitis pigmentosa type 45. Three transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Oct 2013]

CNGB1 Gene-Disease associations (from GenCC):

• CNGB1-related retinopathy

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
• retinitis pigmentosa 45

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P
• retinitis pigmentosa

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 11 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, No cryptic splice site detected. Exon removal results in frameshift change.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 16-57959886-A-T is Pathogenic according to our data. Variant chr16-57959886-A-T is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 437978.Status of the report is no_assertion_criteria_provided, 0 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001297.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CNGB1	NM_001297.5	MANE Select	c.761+2T>A		splice_donor intron	N/A	NP_001288.3
	CNGB1	NM_001286130.2		c.743+2T>A		splice_donor intron	N/A	NP_001273059.1
	CNGB1	NM_001135639.2		c.761+2T>A		splice_donor intron	N/A	NP_001129111.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CNGB1	ENST00000251102.13	TSL:1 MANE Select	c.761+2T>A		splice_donor intron	N/A	ENSP00000251102.8
	CNGB1	ENST00000564448.5	TSL:1	c.743+2T>A		splice_donor intron	N/A	ENSP00000454633.1
	CNGB1	ENST00000311183.8	TSL:1	c.761+2T>A		splice_donor intron	N/A	ENSP00000311670.4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

ClinVar submissions as Germline

Significance: Likely pathogenic

Revision: no assertion criteria provided

Pathogenic	VUS	Benign	Condition
1	-	-	Retinitis pigmentosa (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Benign	-0.23
CADD	Pathogenic	28
DANN	Benign	0.96
Eigen	Pathogenic	0.68
Eigen_PC	Uncertain	0.41
FATHMM_MKL	Uncertain	0.91	D
PhyloP100		3.5
GERP RS		2.8
Mutation Taster		=3/97	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.95
SpliceAI score (max)		0.97		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.97		Position offset: 2

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

Other links and lift over

dbSNP: rs1555493707; hg19: chr16-57993790;