rs104893620

Variant summary

Our verdict is Pathogenic. The variant received 17 ACMG points: 17P and 0B. PM1PM5PP2PP3_StrongPP5_Very_Strong

The NM_001298.3(CNGA3):​c.829C>T​(p.Arg277Cys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000551 in 1,614,100 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R277H) has been classified as Pathogenic.

Frequency

Genomes: 𝑓 0.000072 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000053 ( 0 hom. )

Consequence

CNGA3
NM_001298.3 missense

Scores

16
2
1

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:14

Conservation

PhyloP100: 3.58

Publications

22 publications found
Variant links:
Genes affected
CNGA3 (HGNC:2150): (cyclic nucleotide gated channel subunit alpha 3) This gene encodes a member of the cyclic nucleotide-gated cation channel protein family which is required for normal vision and olfactory signal transduction. Mutations in this gene are associated with achromatopsia (rod monochromacy) and color blindness. Two alternatively spliced transcripts encoding different isoforms have been described. [provided by RefSeq, Jul 2008]
CNGA3 Gene-Disease associations (from GenCC):
  • achromatopsia 2
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae), Illumina, PanelApp Australia
  • CNGA3-related retinopathy
    Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
  • cone-rod dystrophy
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • achromatopsia
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 17 ACMG points.

PM1
In a hotspot region, there are 10 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 3 uncertain in NM_001298.3
PM5
Other missense variant is known to change same aminoacid residue: Variant chr2-98396000-G-A is described in ClinVar as Pathogenic. ClinVar VariationId is 800983.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
PP2
Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 105 curated pathogenic missense variants (we use a threshold of 10). The gene has 14 curated benign missense variants. Trascript score misZ: 0.49806 (below the threshold of 3.09). GenCC associations: The gene is linked to achromatopsia 2, CNGA3-related retinopathy, cone-rod dystrophy, achromatopsia.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.962
PP5
Variant 2-98395999-C-T is Pathogenic according to our data. Variant chr2-98395999-C-T is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 9481.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
CNGA3NM_001298.3 linkc.829C>T p.Arg277Cys missense_variant Exon 8 of 8 ENST00000272602.7 NP_001289.1 Q16281-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CNGA3ENST00000272602.7 linkc.829C>T p.Arg277Cys missense_variant Exon 8 of 8 1 NM_001298.3 ENSP00000272602.2 Q16281-1
CNGA3ENST00000436404.6 linkc.775C>T p.Arg259Cys missense_variant Exon 7 of 7 1 ENSP00000410070.2 Q16281-2
CNGA3ENST00000409937.1 linkn.982C>T non_coding_transcript_exon_variant Exon 8 of 8 2

Frequencies

GnomAD3 genomes
AF:
0.0000723
AC:
11
AN:
152216
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:
0.000192
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000955
AC:
24
AN:
251350
AF XY:
0.000125
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000579
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.0000544
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.000141
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000534
AC:
78
AN:
1461884
Hom.:
0
Cov.:
31
AF XY:
0.0000646
AC XY:
47
AN XY:
727240
show subpopulations
African (AFR)
AF:
0.0000299
AC:
1
AN:
33480
American (AMR)
AF:
0.0000671
AC:
3
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39696
South Asian (SAS)
AF:
0.0000927
AC:
8
AN:
86258
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:
0.0000576
AC:
64
AN:
1112006
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.494
Heterozygous variant carriers
0
6
11
17
22
28
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome 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
GnomAD4 genome
AF:
0.0000723
AC:
11
AN:
152216
Hom.:
0
Cov.:
32
AF XY:
0.0000672
AC XY:
5
AN XY:
74372
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41456
American (AMR)
AF:
0.00
AC:
0
AN:
15278
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.000192
AC:
1
AN:
5206
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4832
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10624
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.000147
AC:
10
AN:
68030
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.557
Heterozygous variant carriers
0
1
2
2
3
4
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:
0.0000975
Hom.:
0
Bravo
AF:
0.0000756
TwinsUK
AF:
0.000270
AC:
1
ALSPAC
AF:
0.00
AC:
0
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.000123
AC:
15
EpiCase
AF:
0.000273
EpiControl
AF:
0.0000593

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:14
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Pathogenic:5
Jul 23, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces arginine, which is basic and polar, with cysteine, which is neutral and slightly polar, at codon 277 of the CNGA3 protein (p.Arg277Cys). This variant is present in population databases (rs104893620, gnomAD 0.02%). This missense change has been observed in individuals with achromatopsia and cone dystrophy (PMID: 11536077). ClinVar contains an entry for this variant (Variation ID: 9481). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt CNGA3 protein function with a positive predictive value of 95%. Experimental studies have shown that this missense change affects CNGA3 function (PMID: 20238023). This variant disrupts the p.Arg277 amino acid residue in CNGA3. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 11536077, 17693388, 26992781). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. For these reasons, this variant has been classified as Pathogenic. -

May 01, 2018
CeGaT Center for Human Genetics Tuebingen
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

-
Clinical Genetics, Academic Medical Center
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Mar 07, 2025
GeneDx
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Published functional studies demonstrate a damaging effect as R277C impaired channel activity compared to wild type CNGA3 (PMID: 17693388); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 20238023, 36833446, 31964843, 34321860, 21912902, 14736794, 14757870, 15712225, 16961972, 18521937, 31589614, 31429209, 32531858, 37734845, 15743887, 21911670, 26992781, 19592100, 24049715, 18445228, 23082193, 30682209, 30653986, 30418171, 31456290, 35119454, 34449556, 11536077, 17693388) -

-
Joint Genome Diagnostic Labs from Nijmegen and Maastricht, Radboudumc and MUMC+
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Achromatopsia 2 Pathogenic:4
Oct 01, 2001
OMIM
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:literature only

- -

May 04, 2022
Mendelics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jul 09, 2020
Baylor Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was determined to be pathogenic according to ACMG Guidelines, 2015 [PMID:25741868]. -

Feb 25, 2022
Fulgent Genetics, Fulgent Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Achromatopsia Pathogenic:2
Mar 20, 2018
Molecular Genetics Laboratory, Institute for Ophthalmic Research
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:research

- -

Jun 23, 2019
Sharon lab, Hadassah-Hebrew University Medical Center
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:research

- -

Optic atrophy Pathogenic:1
Jan 01, 2023
Institute of Human Genetics, Univ. Regensburg, Univ. Regensburg
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Macular degeneration;C0085636:Photophobia;C0234629:Color vision defect Pathogenic:1
Jan 01, 2017
Centre for Mendelian Genomics, University Medical Centre Ljubljana
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Retinal dystrophy Pathogenic:1
Jan 01, 2023
Institute of Human Genetics, Univ. Regensburg, Univ. Regensburg
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.68
BayesDel_addAF
Pathogenic
0.35
D
BayesDel_noAF
Pathogenic
0.53
CADD
Pathogenic
32
DANN
Pathogenic
1.0
DEOGEN2
Pathogenic
0.95
D;.;D;.
Eigen
Pathogenic
0.84
Eigen_PC
Pathogenic
0.74
FATHMM_MKL
Uncertain
0.94
D
LIST_S2
Pathogenic
0.99
D;D;.;D
M_CAP
Pathogenic
0.55
D
MetaRNN
Pathogenic
0.96
D;D;D;D
MetaSVM
Pathogenic
1.0
D
MutationAssessor
Pathogenic
4.2
H;.;H;.
PhyloP100
3.6
PrimateAI
Uncertain
0.63
T
PROVEAN
Pathogenic
-7.0
D;D;D;D
REVEL
Pathogenic
0.95
Sift
Pathogenic
0.0
D;D;D;D
Sift4G
Pathogenic
0.0
D;D;D;D
Polyphen
1.0
D;.;D;.
Vest4
0.83
MVP
1.0
MPC
0.60
ClinPred
0.96
D
GERP RS
5.2
Varity_R
0.89
gMVP
0.98
Mutation Taster
=0/100
disease causing (ClinVar)

Splicing

Name
Calibrated prediction
Score
Prediction
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

Other links and lift over

dbSNP: rs104893620; hg19: chr2-99012462; COSMIC: COSV55622980; API