rs779426136

Variant summary

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

The NM_000350.3(ABCA4):​c.3385C>T​(p.Arg1129Cys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000155 in 1,613,986 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. R1129H) has been classified as Likely pathogenic.

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000015 ( 0 hom. )

Consequence

ABCA4
NM_000350.3 missense

Scores

13
5
1

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:4

Conservation

PhyloP100: 2.63

Publications

16 publications found
Variant links:
Genes affected
ABCA4 (HGNC:34): (ATP binding cassette subfamily A member 4) The membrane-associated protein encoded by this gene is a member of the superfamily of ATP-binding cassette (ABC) transporters. ABC proteins transport various molecules across extra- and intracellular membranes. ABC genes are divided into seven distinct subfamilies (ABC1, MDR/TAP, MRP, ALD, OABP, GCN20, White). This protein is a member of the ABC1 subfamily. Members of the ABC1 subfamily comprise the only major ABC subfamily found exclusively in multicellular eukaryotes. This protein is a retina-specific ABC transporter with N-retinylidene-PE as a substrate. It is expressed exclusively in retina photoreceptor cells, and the gene product mediates transport of an essental molecule, all-trans-retinal aldehyde (atRAL), across the photoreceptor cell membrane. Mutations in this gene are found in patients diagnosed with Stargardt disease, a form of juvenile-onset macular degeneration. Mutations in this gene are also associated with retinitis pigmentosa-19, cone-rod dystrophy type 3, early-onset severe retinal dystrophy, fundus flavimaculatus, and macular degeneration age-related 2. [provided by RefSeq, Sep 2019]
ABCA4 Gene-Disease associations (from GenCC):
  • ABCA4-related retinopathy
    Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
  • cone-rod dystrophy 3
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P, Ambry Genetics
  • severe early-childhood-onset retinal dystrophy
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Laboratory for Molecular Medicine, Labcorp Genetics (formerly Invitae), Ambry Genetics
  • retinitis pigmentosa 19
    Inheritance: AR Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
  • cone-rod dystrophy
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • retinitis pigmentosa
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • Stargardt disease
    Inheritance: AD 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 12 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 9 uncertain in NM_000350.3
PM5
Other missense variant is known to change same aminoacid residue: Variant chr1-94041345-C-T is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 865964.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 578 curated pathogenic missense variants (we use a threshold of 10). The gene has 28 curated benign missense variants. Gene score misZ: -0.65813 (below the threshold of 3.09). Trascript score misZ: 1.3628 (below the threshold of 3.09). GenCC associations: The gene is linked to cone-rod dystrophy 3, retinitis pigmentosa 19, ABCA4-related retinopathy, severe early-childhood-onset retinal dystrophy, cone-rod dystrophy, Stargardt disease, retinitis pigmentosa.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.994
PP5
Variant 1-94041346-G-A is Pathogenic according to our data. Variant chr1-94041346-G-A is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 298251.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
ABCA4NM_000350.3 linkc.3385C>T p.Arg1129Cys missense_variant Exon 23 of 50 ENST00000370225.4 NP_000341.2 P78363Q6AI28
ABCA4NM_001425324.1 linkc.3163C>T p.Arg1055Cys missense_variant Exon 22 of 49 NP_001412253.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
ABCA4ENST00000370225.4 linkc.3385C>T p.Arg1129Cys missense_variant Exon 23 of 50 1 NM_000350.3 ENSP00000359245.3 P78363

Frequencies

GnomAD3 genomes
AF:
0.0000197
AC:
3
AN:
152106
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000655
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:
0.0000294
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000119
AC:
3
AN:
251452
AF XY:
0.00000736
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000289
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000879
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000150
AC:
22
AN:
1461880
Hom.:
0
Cov.:
32
AF XY:
0.0000165
AC XY:
12
AN XY:
727238
show subpopulations
African (AFR)
AF:
0.0000597
AC:
2
AN:
33480
American (AMR)
AF:
0.0000224
AC:
1
AN:
44722
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86256
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53416
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5762
European-Non Finnish (NFE)
AF:
0.0000162
AC:
18
AN:
1112012
Other (OTH)
AF:
0.00
AC:
0
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.498
Heterozygous variant carriers
0
2
3
5
6
8
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:
0.0000197
AC:
3
AN:
152106
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74288
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41412
American (AMR)
AF:
0.0000655
AC:
1
AN:
15278
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5172
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4824
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10610
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000294
AC:
2
AN:
68026
Other (OTH)
AF:
0.00
AC:
0
AN:
2088
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.508
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.0000976
Hom.:
0
Bravo
AF:
0.0000302
ExAC
AF:
0.0000165
AC:
2

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:4
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Pathogenic:2
Jan 28, 2025
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 1129 of the ABCA4 protein (p.Arg1129Cys). This variant is present in population databases (rs779426136, gnomAD 0.003%). This missense change has been observed in individuals with Stargardt disease or cone dystrophy (PMID: 19074458, 25097241, 25312043, 29925512). ClinVar contains an entry for this variant (Variation ID: 298251). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is expected to disrupt ABCA4 protein function with a positive predictive value of 95%. Experimental studies have shown that this missense change affects ABCA4 function (PMID: 26092729). This variant disrupts the p.Arg1129 amino acid residue in ABCA4. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 19074458, 23755871, 27032803, 29114839). 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. -

Mar 25, 2016
GeneDx
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The R1129C variant has been reported previously is association with Stargardt disease (Allikmets et al., 1997; Lewis et al., 1999). In vitro functional studies demonstrated that the presence of the R1129C variant results in decreased expressed ABCA4 protein levels in comparison to wild-type ABCA4 (Sabirzhanova et al., 2015). The R1129C variant was not observed in approximately 6,500 individuals of European and African American ancestry in the NHLBI Exome Sequencing Project, indicating it is not a common benign variant in these populations. The R1129C variant is a non-conservative amino acid substitution, which is likely to impact secondary protein structure as these residues differ in polarity, charge, size and/or other properties. This substitution occurs at a position that is conserved across species. In silico analysis predicts this variant is probably damaging to the protein structure/function. Therefore, this variant is pathogenic. -

Severe early-childhood-onset retinal dystrophy Pathogenic:1
Feb 05, 2025
SingHealth Duke-NUS Institute of Precision Medicine
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant is located in a mutational hotspot where >50% of variants are pathogenic (PM1). Homozygous allele count in gnomAD exomes and genomes is 0 (PM2). Other variants at this amino acid residue have been classified as pathogenic (PM5, p.Arg1129Gly; p.Arg1129His). REVEL score is 0.868 (PP3_mod) -

Retinal dystrophy Pathogenic:1
Jan 01, 2018
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
Uncertain
0.40
BayesDel_addAF
Pathogenic
0.32
D
BayesDel_noAF
Pathogenic
0.32
CADD
Pathogenic
29
DANN
Pathogenic
1.0
DEOGEN2
Pathogenic
0.91
D
Eigen
Pathogenic
0.82
Eigen_PC
Pathogenic
0.75
FATHMM_MKL
Uncertain
0.93
D
LIST_S2
Uncertain
0.97
D
M_CAP
Pathogenic
0.61
D
MetaRNN
Pathogenic
0.99
D
MetaSVM
Uncertain
0.48
D
MutationAssessor
Pathogenic
3.3
M
PhyloP100
2.6
PrimateAI
Uncertain
0.74
T
PROVEAN
Pathogenic
-7.5
D
REVEL
Pathogenic
0.87
Sift
Pathogenic
0.0
D
Sift4G
Pathogenic
0.0
D
Polyphen
1.0
D
Vest4
0.96
MutPred
0.96
Loss of disorder (P = 0.0582);
MVP
0.87
MPC
0.51
ClinPred
1.0
D
GERP RS
5.5
Varity_R
0.81
gMVP
0.89
Mutation Taster
=8/92
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: rs779426136; hg19: chr1-94506902; API