rs1553193813

Variant names:

• chr1-94077747-C-T
• rs1553193813
• NM_000350.3:c.1497G>A

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_000350.3(ABCA4):​c.1497G>A​(p.Trp499*) variant causes a stop gained change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 32)
• Consequence: ABCA4 NM_000350.3 stop_gained
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:4
• Conservation: PhyloP100: 7.52

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]

LOC124904222 (HGNC:):

ACMG classification

Verdict is Pathogenic. Variant got 18 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 1-94077747-C-T is Pathogenic according to our data. Variant chr1-94077747-C-T is described in ClinVar as [Pathogenic]. Clinvar id is 438087.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr1-94077747-C-T is described in Lovd as [Pathogenic]. Variant chr1-94077747-C-T is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
ABCA4	NM_000350.3	c.1497G>A	p.Trp499*	stop_gained	Exon 11 of 50	ENST00000370225.4	NP_000341.2
ABCA4	NM_001425324.1	c.1497G>A	p.Trp499*	stop_gained	Exon 11 of 49		NP_001412253.1
LOC124904222	XR_007066231.1	n.203-5982C>T		intron_variant	Intron 1 of 1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
ABCA4	ENST00000370225.4	c.1497G>A	p.Trp499*	stop_gained	Exon 11 of 50	1	NM_000350.3	ENSP00000359245.3
ABCA4	ENST00000649773.1	c.1497G>A	p.Trp499*	stop_gained	Exon 11 of 19			ENSP00000496882.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Pathogenic:2

Mar 24, 2023

GeneDx

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Nonsense variant predicted to result in protein truncation or nonsense mediated decay in a gene for which loss of function is a known mechanism of disease; Not observed at significant frequency in large population cohorts (gnomAD); This variant is associated with the following publications: (PMID: 32581362, 28041643) -

Sep 25, 2020

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change creates a premature translational stop signal (p.Trp499*) in the ABCA4 gene. It is expected to result in an absent or disrupted protein product. This variant is not present in population databases (ExAC no frequency). This variant has been observed in individual(s) with inherited retinal dystrophy (PMID: 28041643). ClinVar contains an entry for this variant (Variation ID: 438087). Loss-of-function variants in ABCA4 are known to be pathogenic (PMID: 10958761, 24938718, 25312043, 26780318). For these reasons, this variant has been classified as Pathogenic. -

Cone-rod dystrophy 3 Pathogenic:1

Apr 20, 2017

Bioscientia Institut fuer Medizinische Diagnostik GmbH, Sonic Healthcare

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

Retinal dystrophy Pathogenic:1

Jan 01, 2015

NIHR Bioresource Rare Diseases, University of Cambridge

Significance: Likely pathogenic

Review Status: no assertion criteria provided

Collection Method: research

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.62	D
BayesDel_noAF	Pathogenic	0.66
CADD	Pathogenic	38
DANN	Uncertain	1.0
Eigen	Pathogenic	0.83
Eigen_PC	Uncertain	0.66
FATHMM_MKL	Pathogenic	0.98	D
Vest4		0.90
GERP RS		5.2

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

Other links and lift over

dbSNP: rs1553193813; hg19: chr1-94543303;