rs61750648

Positions:

chr1-94001072-G-A

Variant summary

Our verdict is Pathogenic. Variant got 16 ACMG points: 16P and 0B. PM1PM5PP3_StrongPP5_Very_Strong

The NM_000350.3(ABCA4):c.6316C>T(p.Arg2106Cys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000985 in 1,614,108 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. R2106H) has been classified as Likely pathogenic.

Frequency

Genomes: 𝑓 0.00030 ( 0 hom., cov: 33)

Exomes 𝑓: 0.000077 ( 0 hom. )

Consequence

ABCA4
NM_000350.3 missense

Scores

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:9O:1

Conservation

PhyloP100: 2.93

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 16 ACMG points.

PM1

In a hotspot region, there are 8 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 7 uncertain in NM_000350.3

PM5

Other missense variant is known to change same aminoacid residue: Variant chr1-94001071-C-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 377409.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

PP3

MetaRNN computational evidence supports a deleterious effect, 0.952

PP5

Variant 1-94001072-G-A is Pathogenic according to our data. Variant chr1-94001072-G-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 99447.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr1-94001072-G-A is described in Lovd as [Pathogenic]. Variant chr1-94001072-G-A is described in Lovd as [Likely_pathogenic]. Variant chr1-94001072-G-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
ABCA4	NM_000350.3 linkuse as main transcript	c.6316C>T	p.Arg2106Cys	missense_variant	46/50	ENST00000370225.4	NP_000341.2	P78363Q6AI28
ABCA4	XM_047416704.1 linkuse as main transcript	c.6094C>T	p.Arg2032Cys	missense_variant	45/49

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
ABCA4	ENST00000370225.4 linkuse as main transcript	c.6316C>T	p.Arg2106Cys	missense_variant	46/50	1	NM_000350.3	ENSP00000359245.3		P78363

Frequencies

GnomAD3 genomes

AF:

0.000302

AC:

AN:

152178

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.000845

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.000131

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.000207

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.000103

Gnomad OTH

AF:

0.000478

GnomAD3 exomes

AF:

0.0000995

AC:

AN:

251238

Hom.:

AF XY:

0.0000957

AC XY:

AN XY:

135794

show subpopulations

Gnomad AFR exome

AF:

0.000615

Gnomad AMR exome

AF:

0.0000289

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.0000327

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.000114

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000773

AC:

113

AN:

1461812

Hom.:

Cov.:

AF XY:

0.0000715

AC XY:

AN XY:

727198

show subpopulations

Gnomad4 AFR exome

AF:

0.000687

Gnomad4 AMR exome

AF:

0.0000447

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000756

Gnomad4 SAS exome

AF:

0.0000464

Gnomad4 FIN exome

AF:

0.0000562

Gnomad4 NFE exome

AF:

0.0000638

Gnomad4 OTH exome

AF:

0.0000662

GnomAD4 genome

AF:

0.000302

AC:

AN:

152296

Hom.:

Cov.:

AF XY:

0.000336

AC XY:

AN XY:

74478

show subpopulations

Gnomad4 AFR

AF:

0.000842

Gnomad4 AMR

AF:

0.000131

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.000207

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.000103

Gnomad4 OTH

AF:

0.000473

Alfa

AF:

0.000189

Hom.:

Bravo

AF:

0.000280

ESP6500AA

AF:

0.000454

AC:

ESP6500EA

AF:

0.00

AC:

ExAC

AF:

0.000115

AC:

EpiCase

AF:

0.000164

EpiControl

AF:

0.000119

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:9Other:1

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not provided

Pathogenic:3Other:1

Pathogenic, criteria provided, single submitter	clinical testing	Revvity Omics, Revvity	Oct 31, 2019	- -
not provided, no classification provided	literature only	Retina International	-	- -
Pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jan 31, 2024	This sequence change replaces arginine, which is basic and polar, with cysteine, which is neutral and slightly polar, at codon 2106 of the ABCA4 protein (p.Arg2106Cys). This variant is present in population databases (rs61750648, gnomAD 0.08%). This missense change has been observed in individual(s) with Stargardt disease (PMID: 11379881, 23143460, 25283059, 28355279). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. ClinVar contains an entry for this variant (Variation ID: 99447). 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%. Experimental studies have shown that this missense change affects ABCA4 function (PMID: 11017087). This variant disrupts the p.Arg2106 amino acid residue in ABCA4. Other variant(s) that disrupt this residue have been observed in individuals with ABCA4-related conditions (PMID: 26161775, 28327576), which suggests that this may be a clinically significant amino acid residue. For these reasons, this variant has been classified as Pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Nov 19, 2021	In silico analysis, which includes protein predictors and evolutionary conservation, supports a deleterious effect; This variant is associated with the following publications: (PMID: 11379881, 9054934, 23143460, 25066811, 28044389, 28355279, 25283059, 30903310, 34426522, 31589614, 29114839, 32619608) -

Retinal dystrophy

Pathogenic:3

Pathogenic, criteria provided, single submitter	clinical testing	Institute of Human Genetics, Univ. Regensburg, Univ. Regensburg	Jan 01, 2023	- -
Likely pathogenic, criteria provided, single submitter	research	Dept Of Ophthalmology, Nagoya University	Oct 01, 2023	- -
Pathogenic, criteria provided, single submitter	clinical testing	Blueprint Genetics	Dec 04, 2018	- -

Age related macular degeneration 2

Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Institute of Human Genetics, University of Leipzig Medical Center

Oct 18, 2024

Criteria applied: PM3_VSTR,PM5,PM2_SUP,PP3 -

Severe early-childhood-onset retinal dystrophy

Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

MGZ Medical Genetics Center

Dec 20, 2021

- -

Stargardt disease

Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Mar 09, 2017

The p.Arg2106Cys variant in ABCA4 has been reported in at least 5 individuals (compound heterozygotes) with Stargardt disease (Allikmets 1997, Zernant 2011, Downes 2012, Zernant 2014, Schulz 2017). This variant has also been identified in 0.04% (4/10392) of African chromosomes by the Exome Aggregation Consortium (ExAC, http://exac.broadinstitute.org; dbSNP rs61750648). Although this variant has been seen in the general population, its frequency is low enough to be consistent with a recessive carrier frequency. Computational prediction tools and conservation analysis are consistent with pathogenicity. In summary, this variant meets criteria to be classified as pathogenic for Stargardt disease in an autosomal recessive manner based upon case studies and low frequency in controls. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.58

BayesDel_addAF

Pathogenic

0.24

BayesDel_noAF

Pathogenic

0.52

CADD

Pathogenic

DANN

Pathogenic

1.0

DEOGEN2

Uncertain

0.59

D;D

Eigen

Pathogenic

0.89

Eigen_PC

Pathogenic

0.82

FATHMM_MKL

Uncertain

0.95

LIST_S2

Pathogenic

1.0

D;D

M_CAP

Pathogenic

0.37

MetaRNN

Pathogenic

0.95

D;D

MetaSVM

Pathogenic

1.1

MutationAssessor

Pathogenic

3.4

.;M

PrimateAI

Uncertain

0.74

PROVEAN

Pathogenic

-6.8

.;D

REVEL

Pathogenic

0.89

Sift

Pathogenic

0.0

.;D

Sift4G

Pathogenic

0.0

D;D

Polyphen

1.0

.;D

Vest4

0.99

MVP

0.99

MPC

0.54

ClinPred

0.59

GERP RS

5.1

Varity_R

0.93

gMVP

0.93

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.010

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