rs61750152

Positions:

Variant summary

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

The NM_000350.3(ABCA4):c.4577C>T(p.Thr1526Met) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000123 in 1,614,058 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. T1526A) has been classified as Likely pathogenic.

Frequency

Genomes: 𝑓 0.000085 ( 0 hom., cov: 33)

Exomes 𝑓: 0.00013 ( 0 hom. )

Consequence

ABCA4
NM_000350.3 missense

Scores

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:13O:1

Conservation

PhyloP100: 7.91

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:

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 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 4 uncertain in NM_000350.3

PM5

Other missense variant is known to change same aminoacid residue: Variant chr1-94025012-T-C is described in Lovd as [Likely_pathogenic].

PP3

MetaRNN computational evidence supports a deleterious effect, 0.98

PP5

Variant 1-94025011-G-A is Pathogenic according to our data. Variant chr1-94025011-G-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 99303.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr1-94025011-G-A is described in Lovd as [Likely_pathogenic]. Variant chr1-94025011-G-A is described in Lovd as [Pathogenic]. Variant chr1-94025011-G-A is described in Lovd as [Pathogenic]. Variant chr1-94025011-G-A is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
ABCA4	NM_000350.3 linkuse as main transcript	c.4577C>T	p.Thr1526Met	missense_variant	31/50	ENST00000370225.4
ABCA4	XM_047416704.1 linkuse as main transcript	c.4355C>T	p.Thr1452Met	missense_variant	30/49

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
ABCA4	ENST00000370225.4 linkuse as main transcript	c.4577C>T	p.Thr1526Met	missense_variant	31/50	1	NM_000350.3	P1
ABCA4	ENST00000460514.1 linkuse as main transcript	n.71C>T		non_coding_transcript_exon_variant	2/7	5

Frequencies

GnomAD3 genomes

AF:

0.0000854

AC:

AN:

152182

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000241

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

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:

0.000176

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000517

AC:

AN:

251482

Hom.:

AF XY:

0.0000736

AC XY:

AN XY:

135914

show subpopulations

Gnomad AFR exome

AF:

0.0000615

Gnomad AMR exome

AF:

0.00

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:

0.0000967

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.000127

AC:

185

AN:

1461876

Hom.:

Cov.:

AF XY:

0.000102

AC XY:

AN XY:

727244

show subpopulations

Gnomad4 AFR exome

AF:

0.0000299

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.0000464

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.000153

Gnomad4 OTH exome

AF:

0.000166

GnomAD4 genome

AF:

0.0000854

AC:

AN:

152182

Hom.:

Cov.:

AF XY:

0.0000403

AC XY:

AN XY:

74352

show subpopulations

Gnomad4 AFR

AF:

0.0000241

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.000176

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.000136

Hom.:

Bravo

AF:

0.0000869

TwinsUK

AF:

0.000270

AC:

ALSPAC

AF:

0.00

AC:

ExAC

AF:

0.0000330

AC:

EpiCase

AF:

0.000164

EpiControl

AF:

0.0000593

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:13Other:1

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Severe early-childhood-onset retinal dystrophy

Pathogenic:4

Likely pathogenic, criteria provided, single submitter	research	Ocular Genomics Institute, Massachusetts Eye and Ear	Apr 08, 2021	The ABCA4 c.4577C>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: PS3, PM2, PP3, PP5. Based on this evidence we have classified this variant as Likely Pathogenic. -
Likely pathogenic, no assertion criteria provided	research	NIHR Bioresource Rare Diseases, University of Cambridge	Jan 01, 2015	- -
Pathogenic, criteria provided, single submitter	clinical testing	Molecular Genetics, Royal Melbourne Hospital	Mar 30, 2023	This sequence change is predicted to replace threonine with methionine at codon 1526 of the ABCA4 protein, p.(Thr1526Met). The threonine residue is moderately conserved (100 vertebrates, UCSC), and in the extracellular domain. There is a moderate physicochemical difference between threonine and methionine. The variant is present in a large population cohort at a frequency of 0.006%, which is consistent with recessive disease (rs61750152, 18/282,882 alleles, 0 homozygotes in gnomAD v2.1.1). Multiple Stargardt disease/ABCA4 retinopathy cases are compound heterozygous with a second pathogenic variant or homozygous (PMID: 9973280, 19074458, 28446513), and at least two affected segregations in a single family have been reported for the variant (PMID: 19074458). Multiple lines of computational evidence predict a deleterious effect for the missense substitution (7/7 algorithms). Based on the classification scheme RMH ACMG Guidelines v1.1.1, this variant is classified as PATHOGENIC. Following criteria are met: PM3_VeryStrong, PM2, PP1, PP3. -
Pathogenic, no assertion criteria provided	research	Ophthalmo-Genetics Lab, Instituto de Oftalmologia Conde de Valenciana	-	- -

not provided

Pathogenic:3Other:1

Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Jan 07, 2023	Published functional studies demonstrate reduced basal ATPase activity and almost absent retinal-stimulated activity (Sun et al., 2000); 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: 30653986, 34240658, 34758253, 32467599, 11527935, 21558428, 23918662, 11702214, 11726554, 23755871, 19265867, 21911583, 14517951, 9973280, 26551331, 23982839, 23143460, 30337596, 29925512, 28559085, 31456290, 32581362, 31618761, 32845068, 33301772, 32037395, 35119454, 35409265, 11017087, 19074458, 25082885) -
Pathogenic, criteria provided, single submitter	clinical testing	Eurofins Ntd Llc (ga)	Feb 12, 2015	- -
not provided, no classification provided	literature only	Retina International	-	- -
Pathogenic, criteria provided, single submitter	clinical testing	Invitae	Jan 29, 2024	This sequence change replaces threonine, which is neutral and polar, with methionine, which is neutral and non-polar, at codon 1526 of the ABCA4 protein (p.Thr1526Met). This variant is present in population databases (rs61750152, gnomAD 0.01%). This missense change has been observed in individuals with Stargardt disease or cone-rod dystrophy and Stargardt disease in at least one family and has been observed in unrelated individuals affected with Stargardt disease or cone-rod dystrophy (PMID: 9973280, 19074458). It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 99303). 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). For these reasons, this variant has been classified as Pathogenic. -

Retinitis pigmentosa 19

Pathogenic:2

Likely pathogenic, no assertion criteria provided	clinical testing	Centre for Genomic Medicine, Manchester, Central Manchester University Hospitals	Jan 23, 2015	- -
Likely pathogenic, no assertion criteria provided	clinical testing	Genomics England Pilot Project, Genomics England	-	- -

Age related macular degeneration 2

Pathogenic:1

Pathogenic, no assertion criteria provided

clinical testing

Genomics England Pilot Project, Genomics England

- -

Inborn genetic diseases

Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Ambry Genetics

Oct 31, 2017

- -

Retinal dystrophy

Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Blueprint Genetics

Aug 02, 2019

- -

Stargardt disease

Pathogenic:1

Pathogenic, no assertion criteria provided

research

Sharon lab, Hadassah-Hebrew University Medical Center

Jun 23, 2019

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Uncertain

0.37

BayesDel_addAF

Pathogenic

0.37

BayesDel_noAF

Pathogenic

0.51

CADD

Uncertain

DANN

Pathogenic

1.0

DEOGEN2

Uncertain

0.47

T;D

Eigen

Uncertain

0.55

Eigen_PC

Uncertain

0.42

FATHMM_MKL

Pathogenic

0.97

LIST_S2

Pathogenic

0.99

D;D

M_CAP

Pathogenic

0.57

MetaRNN

Pathogenic

0.98

D;D

MetaSVM

Pathogenic

1.0

MutationTaster

Benign

1.0

PrimateAI

Uncertain

0.59

Sift4G

Pathogenic

0.0010

D;D

Polyphen

1.0

.;D

Vest4

0.92

MutPred

0.88

.;Loss of helix (P = 0.028);

MVP

0.97

MPC

0.44

ClinPred

0.86

GERP RS

4.0

Varity_R

0.64

gMVP

0.70

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