rs121909205

Positions:

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

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]

ABCA4 links:

ABCA4 (HGNC:):

ABCA4 links:

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/exons	MANE	Protein	UniProt
ABCA4	NM_000350.3 linkuse as main transcript	c.52C>T	p.Arg18Trp	missense_variant	1/50	ENST00000370225.4	NP_000341.2	P78363Q6AI28
ABCA4	XM_047416704.1 linkuse as main transcript	c.52C>T	p.Arg18Trp	missense_variant	1/49

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
ABCA4	ENST00000370225.4 linkuse as main transcript	c.52C>T	p.Arg18Trp	missense_variant	1/50	1	NM_000350.3	ENSP00000359245.3		P78363
ABCA4	ENST00000649773.1 linkuse as main transcript	c.52C>T	p.Arg18Trp	missense_variant	1/19			ENSP00000496882.1		A0A3B3IRV8

Frequencies

GnomAD3 genomes

AF:

0.0000606

AC:

AN:

148518

Hom.:

Cov.:

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:

AN:

251400

Hom.:

AF XY:

0.0000221

AC XY:

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:

AN:

1457948

Hom.:

Cov.:

AF XY:

0.00000552

AC XY:

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:

AN:

148632

Hom.:

Cov.:

AF XY:

0.0000416

AC XY:

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.:

Bravo

AF:

0.000144

ESP6500AA

AF:

0.00

AC:

ESP6500EA

AF:

0.000233

AC:

ExAC

AF:

0.0000247

AC:

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

Pathogenic, criteria provided, single submitter	clinical testing	Eurofins Ntd Llc (ga)	Sep 28, 2016	- -
not provided, no classification provided	literature only	Retina International	-	- -
Pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jan 30, 2024	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). 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 ABCA4 protein function with a positive predictive value of 95%. For these reasons, this variant has been classified as Pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	May 17, 2024	Not observed at a 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) -
Pathogenic, criteria provided, single submitter	clinical testing	CeGaT Center for Human Genetics Tuebingen	Jun 01, 2021	- -
Pathogenic, criteria provided, single submitter	clinical testing	Institute of Medical Genetics and Applied Genomics, University Hospital Tübingen	Oct 23, 2020	- -

Severe early-childhood-onset retinal dystrophy

Pathogenic:2

Pathogenic, no assertion criteria provided	literature only	OMIM	Feb 15, 1998	- -
Pathogenic, criteria provided, single submitter	research	Ocular Genomics Institute, Massachusetts Eye and Ear	Apr 08, 2021	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. -

Retinal dystrophy

Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Blueprint Genetics	May 09, 2019	- -
Pathogenic, criteria provided, single submitter	clinical testing	Institute of Human Genetics, Univ. Regensburg, Univ. Regensburg	Jan 01, 2017	- -

Stargardt disease 3

Pathogenic:1

Pathogenic, no assertion criteria provided

research

Ophthalmo-Genetics Lab, Instituto de Oftalmologia Conde de Valenciana

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.25

BayesDel_addAF

Pathogenic

0.33

BayesDel_noAF

Pathogenic

0.32

CADD

Benign

DANN

Uncertain

1.0

DEOGEN2

Pathogenic

0.82

D;.

Eigen

Benign

0.0057

Eigen_PC

Benign

-0.18

FATHMM_MKL

Benign

0.47

LIST_S2

Pathogenic

0.98

D;D

M_CAP

Pathogenic

0.33

MetaRNN

Uncertain

0.67

D;D

MetaSVM

Uncertain

0.72

MutationAssessor

Pathogenic

3.3

M;.

PrimateAI

Uncertain

0.75

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

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.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over