rs121909205

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PM1PM5PP5_Very_Strong

The NM_000350.3(ABCA4):​c.52C>T​(p.Arg18Trp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000137 in 1,606,580 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R18P) has been classified as Likely pathogenic.

Frequency

Genomes: 𝑓 0.000061 ( 0 hom., cov: 31)
Exomes 𝑓: 0.0000089 ( 0 hom. )

Consequence

ABCA4
NM_000350.3 missense

Scores

10
4
5

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:10O:1

Conservation

PhyloP100: 0.243
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 12 ACMG points.

PM1
In a hotspot region, there are 6 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 4 uncertain in NM_000350.3
PM5
Other missense variant is known to change same aminoacid residue: Variant chr1-94120993-C-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 866562.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
PP5
Variant 1-94120994-G-A is Pathogenic according to our data. Variant chr1-94120994-G-A is described in ClinVar as [Pathogenic]. Clinvar id is 7899.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr1-94120994-G-A is described in Lovd as [Likely_pathogenic]. Variant chr1-94120994-G-A is described in Lovd as [Pathogenic]. Variant chr1-94120994-G-A is described in Lovd as [Pathogenic]. Variant chr1-94120994-G-A is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
ABCA4NM_000350.3 linkc.52C>T p.Arg18Trp missense_variant Exon 1 of 50 ENST00000370225.4 NP_000341.2 P78363Q6AI28
ABCA4NM_001425324.1 linkc.52C>T p.Arg18Trp missense_variant Exon 1 of 49 NP_001412253.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
ABCA4ENST00000370225.4 linkc.52C>T p.Arg18Trp missense_variant Exon 1 of 50 1 NM_000350.3 ENSP00000359245.3 P78363
ABCA4ENST00000649773.1 linkc.52C>T p.Arg18Trp missense_variant Exon 1 of 19 ENSP00000496882.1 A0A3B3IRV8

Frequencies

GnomAD3 genomes
AF:
0.0000606
AC:
9
AN:
148518
Hom.:
0
Cov.:
31
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000345
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:
0.0000591
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000159
AC:
4
AN:
251400
Hom.:
0
AF XY:
0.0000221
AC XY:
3
AN XY:
135882
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 SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000176
Gnomad OTH exome
AF:
0.000163
GnomAD4 exome
AF:
0.00000892
AC:
13
AN:
1457948
Hom.:
0
Cov.:
33
AF XY:
0.00000552
AC XY:
4
AN XY:
725230
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.0000673
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00000631
Gnomad4 OTH exome
AF:
0.0000499
GnomAD4 genome
AF:
0.0000606
AC:
9
AN:
148632
Hom.:
0
Cov.:
31
AF XY:
0.0000416
AC XY:
3
AN XY:
72158
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.000345
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000591
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000630
Hom.:
0
Bravo
AF:
0.000144
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000233
AC:
2
ExAC
AF:
0.0000247
AC:
3
EpiCase
AF:
0.00
EpiControl
AF:
0.0000593

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:10Other:1
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Pathogenic:5Other:1
-
Retina International
Significance: not provided
Review Status: no classification provided
Collection Method: literature only

- -

Mar 05, 2025
GeneDx
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Not observed at significant frequency in large population cohorts (gnomAD); 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: 9503029, 28044389, 10090887, 23755871, 28118664, 27014590, 31589614, 30204727, 29925512, 29555955, 37734845, 35120629, 35119454, 35260635, 36460718, 34906470, 38219857, 38309476, 39162841, 38369462) -

Sep 28, 2016
Eurofins Ntd Llc (ga)
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Oct 23, 2020
Institute of Medical Genetics and Applied Genomics, University Hospital Tübingen
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Jun 01, 2021
CeGaT Center for Human Genetics Tuebingen
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Nov 08, 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 tryptophan, which is neutral and slightly polar, at codon 18 of the ABCA4 protein (p.Arg18Trp). This variant is present in population databases (rs121909205, gnomAD 0.003%). This missense change has been observed in individuals with Stargardt disease and retinal disease (PMID: 23096905, 23755871, 29854428, 29925512). It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 7899). 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%. For these reasons, this variant has been classified as Pathogenic. -

Severe early-childhood-onset retinal dystrophy Pathogenic:2
Apr 08, 2021
Ocular Genomics Institute, Massachusetts Eye and Ear
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: research

The ABCA4 c.52C>T variant was identified in an individual with retinitis pigmentosa with a presumed recessive inheritance pattern. Through a review of available evidence we were able to apply the following criteria: PM2, PP3, PM1, PP1, PM3-S. Based on this evidence we have classified this variant as Pathogenic. -

Feb 15, 1998
OMIM
Significance: Pathogenic
Review Status: no assertion criteria provided
Collection Method: literature only

- -

Retinal dystrophy Pathogenic:2
May 09, 2019
Blueprint Genetics
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Jan 01, 2017
Institute of Human Genetics, Univ. Regensburg, Univ. Regensburg
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Stargardt disease 3 Pathogenic:1
-
Ophthalmo-Genetics Lab, Instituto de Oftalmologia Conde de Valenciana
Significance: Pathogenic
Review Status: no assertion criteria provided
Collection Method: research

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.25
BayesDel_addAF
Pathogenic
0.33
D
BayesDel_noAF
Pathogenic
0.32
CADD
Benign
22
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.82
D;.
Eigen
Benign
0.0057
Eigen_PC
Benign
-0.18
FATHMM_MKL
Benign
0.47
N
LIST_S2
Pathogenic
0.98
D;D
M_CAP
Pathogenic
0.33
D
MetaRNN
Uncertain
0.67
D;D
MetaSVM
Uncertain
0.72
D
MutationAssessor
Pathogenic
3.3
M;.
PrimateAI
Uncertain
0.75
T
PROVEAN
Pathogenic
-6.3
D;.
REVEL
Pathogenic
0.77
Sift
Pathogenic
0.0
D;.
Sift4G
Pathogenic
0.0
D;.
Polyphen
1.0
D;.
Vest4
0.92
MVP
0.95
MPC
0.47
ClinPred
0.98
D
GERP RS
-1.9
Varity_R
0.41
gMVP
0.84

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

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs121909205; hg19: chr1-94586550; API