NM_001297.5:c.2978G>A

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PM5PP3

The NM_001297.5(CNGB1):​c.2978G>A​(p.Gly993Glu) variant causes a missense, splice region change. The variant allele was found at a frequency of 0.000137 in 1,614,050 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 2/3 splice prediction tools predicting alterations to normal splicing. 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. G993V) has been classified as Pathogenic.

Frequency

Genomes: 𝑓 0.000059 ( 0 hom., cov: 32)
Exomes 𝑓: 0.00015 ( 0 hom. )

Consequence

CNGB1
NM_001297.5 missense, splice_region

Scores

13
5
Splicing: ADA: 0.9917
2

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 5.98

Publications

8 publications found
Variant links:
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

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 3 ACMG points.

PM5
Other missense variant is known to change same aminoacid residue: Variant chr16-57897913-C-A is described in ClinVar as Pathogenic. ClinVar VariationId is 8897.Status of the report is no_assertion_criteria_provided, 0 stars.
PP3
Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF. No scorers claiming Uncertain. Scorers claiming Benign: max_spliceai.

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
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
CNGB1
NM_001297.5
MANE Select
c.2978G>Ap.Gly993Glu
missense splice_region
Exon 30 of 33NP_001288.3
CNGB1
NM_001286130.2
c.2960G>Ap.Gly987Glu
missense splice_region
Exon 30 of 33NP_001273059.1

Ensembl Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
CNGB1
ENST00000251102.13
TSL:1 MANE Select
c.2978G>Ap.Gly993Glu
missense splice_region
Exon 30 of 33ENSP00000251102.8
CNGB1
ENST00000564448.5
TSL:1
c.2960G>Ap.Gly987Glu
missense splice_region
Exon 30 of 33ENSP00000454633.1
CNGB1
ENST00000565942.1
TSL:5
c.23G>Ap.Gly8Glu
missense splice_region
Exon 2 of 4ENSP00000455964.1

Frequencies

GnomAD3 genomes
AF:
0.0000591
AC:
9
AN:
152212
Hom.:
0
Cov.:
32
show subpopulations
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:
0.000132
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000280
AC:
7
AN:
249556
AF XY:
0.0000443
show subpopulations
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:
0.0000530
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.000145
AC:
212
AN:
1461838
Hom.:
0
Cov.:
32
AF XY:
0.000139
AC XY:
101
AN XY:
727230
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33478
American (AMR)
AF:
0.0000224
AC:
1
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39698
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:
5768
European-Non Finnish (NFE)
AF:
0.000177
AC:
197
AN:
1111964
Other (OTH)
AF:
0.000215
AC:
13
AN:
60394
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.487
Heterozygous variant carriers
0
10
20
30
40
50
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
10
20
30
40
50
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000591
AC:
9
AN:
152212
Hom.:
0
Cov.:
32
AF XY:
0.0000269
AC XY:
2
AN XY:
74360
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41448
American (AMR)
AF:
0.00
AC:
0
AN:
15288
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5198
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4834
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10614
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.000132
AC:
9
AN:
68038
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.447
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.000130
Hom.:
0
Bravo
AF:
0.0000680
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000120
AC:
1
ExAC
AF:
0.0000331
AC:
4
EpiCase
AF:
0.000164
EpiControl
AF:
0.0000593

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Uncertain:2
Nov 20, 2013
Eurofins Ntd Llc (ga)
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Dec 16, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces glycine, which is neutral and non-polar, with glutamic acid, which is acidic and polar, at codon 993 of the CNGB1 protein (p.Gly993Glu). This variant is present in population databases (rs121918532, gnomAD 0.007%). This variant has not been reported in the literature in individuals affected with CNGB1-related conditions. ClinVar contains an entry for this variant (Variation ID: 93702). An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be disruptive. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance.

Retinitis pigmentosa Uncertain:1
Apr 27, 2017
Illumina Laboratory Services, Illumina
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases did not allow this variant to be ruled in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance.

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.96
BayesDel_addAF
Pathogenic
0.42
D
BayesDel_noAF
Pathogenic
0.52
CADD
Pathogenic
33
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.74
D
Eigen
Pathogenic
1.0
Eigen_PC
Pathogenic
0.91
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.95
D
M_CAP
Uncertain
0.28
D
MetaRNN
Pathogenic
0.92
D
MetaSVM
Pathogenic
1.0
D
MutationAssessor
Pathogenic
3.9
H
PhyloP100
6.0
PrimateAI
Pathogenic
0.88
D
PROVEAN
Pathogenic
-7.6
D
REVEL
Pathogenic
0.94
Sift
Pathogenic
0.0
D
Sift4G
Uncertain
0.0030
D
Polyphen
1.0
D
Vest4
0.73
MVP
0.82
MPC
0.56
ClinPred
1.0
D
GERP RS
5.5
Varity_R
0.94
gMVP
0.60
Mutation Taster
=43/57
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Pathogenic
0.99
dbscSNV1_RF
Pathogenic
0.91
SpliceAI score (max)
0.060
Details are displayed if max score is > 0.2

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

Publications

Other links and lift over

dbSNP: rs121918532; hg19: chr16-57931817; API