1-94014665-G-C

Position:

chr1-94014665-G-C

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PM1PP3_ModeratePP5

The ENST00000370225.4(ABCA4):c.5338C>G(p.Pro1780Ala) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000133 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 Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.00013 ( 0 hom., cov: 32)

Exomes 𝑓: 0.00013 ( 0 hom. )

Consequence

ABCA4
ENST00000370225.4 missense

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:5U:6

Conservation

PhyloP100: 10.0

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 Uncertain_significance. Variant got 5 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, 5 uncertain in ENST00000370225.4

PP3

MetaRNN computational evidence supports a deleterious effect, 0.896

PP5

Variant 1-94014665-G-C is Pathogenic according to our data. Variant chr1-94014665-G-C is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 7912.We mark this variant Likely_pathogenic, oryginal submissions are: {Likely_pathogenic=1, Pathogenic=1, Uncertain_significance=6}. Variant chr1-94014665-G-C 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.5338C>G	p.Pro1780Ala	missense_variant	38/50	ENST00000370225.4	NP_000341.2
ABCA4	XM_047416704.1 linkuse as main transcript	c.5116C>G	p.Pro1706Ala	missense_variant	37/49		XP_047272660.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
ABCA4	ENST00000370225.4 linkuse as main transcript	c.5338C>G	p.Pro1780Ala	missense_variant	38/50	1	NM_000350.3	ENSP00000359245	P1

Frequencies

GnomAD3 genomes

AF:

0.000131

AC:

AN:

152176

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000483

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:

0.000265

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.000107

AC:

AN:

251452

Hom.:

AF XY:

0.000125

AC XY:

AN XY:

135890

show subpopulations

Gnomad AFR exome

AF:

0.000123

Gnomad AMR exome

AF:

0.00

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:

0.000211

Gnomad OTH exome

AF:

0.000163

GnomAD4 exome

AF:

0.000133

AC:

194

AN:

1461882

Hom.:

Cov.:

AF XY:

0.000138

AC XY:

100

AN XY:

727240

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.0000374

Gnomad4 NFE exome

AF:

0.000169

Gnomad4 OTH exome

AF:

0.0000662

GnomAD4 genome

AF:

0.000131

AC:

AN:

152176

Hom.:

Cov.:

AF XY:

0.000135

AC XY:

AN XY:

74334

show subpopulations

Gnomad4 AFR

AF:

0.0000483

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:

0.000265

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.000188

Hom.:

Bravo

AF:

0.000166

TwinsUK

AF:

0.00

AC:

ALSPAC

AF:

0.000259

AC:

ESP6500AA

AF:

0.000227

AC:

ESP6500EA

AF:

0.000349

AC:

ExAC

AF:

0.000115

AC:

EpiCase

AF:

0.000164

EpiControl

AF:

0.000119

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:5Uncertain:6

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

not provided

Pathogenic:2Uncertain:1

Pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jan 29, 2024	This sequence change replaces proline, which is neutral and non-polar, with alanine, which is neutral and non-polar, at codon 1780 of the ABCA4 protein (p.Pro1780Ala). This variant is present in population databases (rs121909207, gnomAD 0.02%). This missense change has been observed in individual(s) with Stargardt disease (PMID: 10746567, 28559085). 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: 7912). 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. -
Uncertain significance, criteria provided, single submitter	clinical testing	GeneDx	Apr 26, 2023	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: 20849526, 28559085, 32531858, 10746567, 35886001) -
Likely pathogenic, criteria provided, single submitter	clinical testing	CeGaT Center for Human Genetics Tuebingen	May 01, 2018	- -

Severe early-childhood-onset retinal dystrophy

Pathogenic:1Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	MGZ Medical Genetics Center	Feb 07, 2022	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Centogene AG - the Rare Disease Company	Sep 04, 2018	- -
Pathogenic, no assertion criteria provided	literature only	OMIM	Feb 01, 2000	- -

Retinal dystrophy

Pathogenic:1Uncertain:1

Uncertain significance, criteria provided, single submitter	clinical testing	Blueprint Genetics	Dec 12, 2018	- -
Likely pathogenic, criteria provided, single submitter	clinical testing	Institute of Human Genetics, Univ. Regensburg, Univ. Regensburg	Jan 01, 2022	- -

Optic atrophy

Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Institute of Human Genetics, Univ. Regensburg, Univ. Regensburg

Jan 01, 2022

- -

not specified

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Jun 06, 2023

Variant summary: ABCA4 c.5338C>G (p.Pro1780Ala) results in a non-conservative amino acid change located in the ABC-2 type transporter, transmembrane domain (IPR013525) of the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 0.00011 in 251452 control chromosomes, predominantly at a frequency of 0.00021 within the Non-Finnish European subpopulation in the gnomAD database. This frequency is not significantly higher than estimated for a pathogenic variant in ABCA4 causing Stargardt Disease (0.00011 vs 0.0014), allowing no conclusion about variant significance. c.5338C>G has been reported in the literature as a compound heterozygous genotype in individuals affected with Stargardt Disease (e.g. Shroyer_2000, Stone_2017, Weisschuh_2020). These data indicate that the variant may be associated with disease. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. The following publications have been ascertained in the context of this evaluation (PMID: 35886001, 10746567, 28559085, 32531858). Seven submitters have provided clinical-significance assessments for this variant to ClinVar after 2014 and classified the variant as VUS (n=5) or pathogenic (n=1)/likely pathogenic (n=1). Based on the evidence outlined above, the variant was classified as VUS-possibly pathogenic until additional clinical and/or functional data becomes available. -

ABCA4-related disorder

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Nov 19, 2018

The ABCA4 c.5338C>G (p.Pro1780Ala) missense variant has been reported in one study in which it is found in one individual with Stargardt disease in a compound heterozygous state (Shroyer et al., 2000). The variant has not been reported in the literature in association with any other disease. The p.Pro1780Ala variant was absent from 101 control individuals and is reported at a frequency of 0.000349 in the European American population of the Exome Sequencing Project. Based on the evidence, the p.Pro1780Ala variant is classified as a variant of unknown significance but suspicious for pathogenicity for ABCA4-related disorders. This variant was observed by ICSL as part of a predisposition screen in an ostensibly healthy population. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Uncertain

0.47

BayesDel_addAF

Pathogenic

0.22

BayesDel_noAF

Pathogenic

0.39

CADD

Pathogenic

DANN

Uncertain

0.99

DEOGEN2

Uncertain

0.67

D;D

Eigen

Pathogenic

0.87

Eigen_PC

Pathogenic

0.83

FATHMM_MKL

Uncertain

0.96

LIST_S2

Pathogenic

1.0

D;D

M_CAP

Uncertain

0.13

MetaRNN

Pathogenic

0.90

D;D

MetaSVM

Uncertain

0.53

MutationAssessor

Pathogenic

3.3

.;M

MutationTaster

Benign

1.0

A;A

PrimateAI

Uncertain

0.68

PROVEAN

Pathogenic

-7.4

.;D

REVEL

Pathogenic

0.90

Sift

Uncertain

0.0030

.;D

Sift4G

Benign

0.070

T;D

Polyphen

1.0

.;D

Vest4

0.94

MVP

0.98

MPC

0.46

ClinPred

0.97

GERP RS

4.7

Varity_R

0.83

gMVP

0.86

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