1-94047018-G-C

Position:

chr1-94047018-G-C

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM1BP4_Strong

The ENST00000370225.4(ABCA4):c.2819C>G(p.Pro940Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000631 in 1,614,002 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. 15/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Synonymous variant affecting the same amino acid position (i.e. P940P) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.00032 ( 0 hom., cov: 32)

Exomes 𝑓: 0.00066 ( 1 hom. )

Consequence

ABCA4
ENST00000370225.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:9

Conservation

PhyloP100: 0.784

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 Likely_benign. Variant got -2 ACMG points.

PM1

In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 7 uncertain in ENST00000370225.4

BP4

Computational evidence support a benign effect (MetaRNN=0.060242355).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
ABCA4	NM_000350.3 linkuse as main transcript	c.2819C>G	p.Pro940Arg	missense_variant	19/50	ENST00000370225.4	NP_000341.2
ABCA4	XM_047416704.1 linkuse as main transcript	c.2597C>G	p.Pro866Arg	missense_variant	18/49		XP_047272660.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
ABCA4	ENST00000370225.4 linkuse as main transcript	c.2819C>G	p.Pro940Arg	missense_variant	19/50	1	NM_000350.3	ENSP00000359245	P1
ABCA4	ENST00000649773.1 linkuse as main transcript	c.2597C>G	p.Pro866Arg	missense_variant	18/19			ENSP00000496882

Frequencies

GnomAD3 genomes

AF:

0.000322

AC:

AN:

152116

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.000121

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:

0.000632

Gnomad OTH

AF:

0.000478

GnomAD3 exomes

AF:

0.000263

AC:

AN:

251428

Hom.:

AF XY:

0.000228

AC XY:

AN XY:

135882

show subpopulations

Gnomad AFR exome

AF:

0.0000615

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:

0.000554

Gnomad OTH exome

AF:

0.000163

GnomAD4 exome

AF:

0.000664

AC:

970

AN:

1461886

Hom.:

Cov.:

AF XY:

0.000627

AC XY:

456

AN XY:

727242

show subpopulations

Gnomad4 AFR exome

AF:

0.000119

Gnomad4 AMR exome

AF:

0.0000224

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:

0.000852

Gnomad4 OTH exome

AF:

0.000298

GnomAD4 genome

AF:

0.000322

AC:

AN:

152116

Hom.:

Cov.:

AF XY:

0.000350

AC XY:

AN XY:

74296

show subpopulations

Gnomad4 AFR

AF:

0.000121

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:

0.000632

Gnomad4 OTH

AF:

0.000478

Alfa

AF:

0.000514

Hom.:

Bravo

AF:

0.000246

TwinsUK

AF:

0.00108

AC:

ALSPAC

AF:

0.000519

AC:

ESP6500AA

AF:

0.00

AC:

ESP6500EA

AF:

0.000581

AC:

ExAC

AF:

0.000239

AC:

EpiCase

AF:

0.000491

EpiControl

AF:

0.000711

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:9

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not provided

Uncertain:4

Uncertain significance, no assertion criteria provided	clinical testing	Clinical Genetics, Academic Medical Center	-	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Oct 18, 2022	This sequence change replaces proline, which is neutral and non-polar, with arginine, which is basic and polar, at codon 940 of the ABCA4 protein (p.Pro940Arg). This variant is present in population databases (rs144995371, gnomAD 0.06%). This missense change has been observed in individual(s) with macular degeneration and/or Stargardt disease (PMID: 10634626, 18024811, 30060493; Invitae). ClinVar contains an entry for this variant (Variation ID: 286835). 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 not expected to disrupt ABCA4 protein function. Experimental studies have shown that this missense change affects ABCA4 function (PMID: 11919200, 23144455). In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -
Uncertain significance, criteria provided, single submitter	clinical testing	Eurofins Ntd Llc (ga)	Mar 17, 2016	- -
Uncertain significance, no assertion criteria provided	clinical testing	Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center	-	- -

Retinal dystrophy

Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Blueprint Genetics	Sep 01, 2017	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Institute of Human Genetics, Univ. Regensburg, Univ. Regensburg	Jan 01, 2013	- -

ABCA4-related disorder

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 30, 2018

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). Publications were found based on this search. However, the evidence from the literature, in combination with allele frequency data from public databases where available, was not sufficient to rule this variant in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance. -

Cone-rod dystrophy 3

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Victorian Clinical Genetics Services, Murdoch Childrens Research Institute

Feb 02, 2022

Based on the classification scheme VCGS_Germline_v1.1.1, this variant is classified as 3A-VUS. Following criteria are met: 0102 - Loss-of-function is a known mechanism of disease for this gene. (N) 0108 - This gene is known to be associated with both recessive and dominant disease (OMIM). (N) 0200 - Variant is predicted to result in a missense amino acid change from proline to arginine (exon 19). (N) 0251 - Variant is heterozygous. (N) 0302 - Variant is present in gnomAD <0.001 (80 Heterozygous, 0 Homozygous). (P) 0309 - An alternative amino acid change at the same position has been observed in gnomAD (1 Heterozygous, 0 Homozygous). (N) 0502 - Missense variant with conflicting in silico predictions and low conservation. (N) 0600 - Variant is located in an annotated domain or motif (NBD1 domain; PMID: 11919200). (N) 0705 - No comparable variants have previous evidence for pathogenicity. (N) 0808 - Previous reports of pathogenicity are inconclusive (ClinVar; PMID: 21911583; PMID: 18024811; PMID: 30060493). (N) 0905 - No segregation evidence has been identified for this variant. (N) 1002 - Moderate functional evidence supporting abnormal protein function (PMID: 23144455). (P) 1208 - Inheritance information for this variant is not currently available. (N) Legend: (P) - Pathogenic, (N) - Neutral, (B) - Benign -

Severe early-childhood-onset retinal dystrophy;C1858806:Cone-rod dystrophy 3;C1866422:Retinitis pigmentosa 19;C3495438:Age related macular degeneration 2

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Fulgent Genetics, Fulgent Genetics

Sep 22, 2021

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.095

BayesDel_addAF

Benign

-0.23

BayesDel_noAF

Benign

-0.20

CADD

Benign

DANN

Benign

0.69

DEOGEN2

Benign

0.30

T;.

Eigen

Benign

-0.81

Eigen_PC

Benign

-0.73

FATHMM_MKL

Benign

0.15

LIST_S2

Benign

0.70

T;T

M_CAP

Uncertain

0.10

MetaRNN

Benign

0.060

T;T

MetaSVM

Benign

-0.75

MutationAssessor

Benign

0.47

N;.

MutationTaster

Benign

1.0

N;N

PrimateAI

Benign

0.36

PROVEAN

Benign

-0.18

N;.

REVEL

Benign

0.27

Sift

Benign

0.29

T;.

Sift4G

Benign

0.40

T;.

Polyphen

0.0010

B;.

Vest4

0.23

MVP

0.74

MPC

0.089

ClinPred

0.041

GERP RS

2.3

Varity_R

0.081

gMVP

0.63

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