rs61750138

Variant summary

Our verdict is Likely pathogenic. Variant got 9 ACMG points: 9P and 0B. PP3PP5_Very_Strong

The NM_000350.3(ABCA4):c.4253+5G>T variant causes a splice donor 5th base, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000105 in 1,613,796 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 2/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Pathogenic (★★).

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000010 ( 0 hom. )

Consequence

ABCA4
NM_000350.3 splice_donor_5th_base, intron

Scores

Splicing: ADA: 0.9988

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:5O:1

Conservation

PhyloP100: 0.861

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_pathogenic. Variant got 9 ACMG points.

PP3

Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF. Scorers claiming Uncertain: max_spliceai. No scorers claiming Benign.

PP5

Variant 1-94030991-C-A is Pathogenic according to our data. Variant chr1-94030991-C-A is described in ClinVar as [Pathogenic]. Clinvar id is 99267.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr1-94030991-C-A is described in Lovd as [Likely_pathogenic]. Variant chr1-94030991-C-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.4253+5G>T		splice_donor_5th_base_variant, intron_variant		ENST00000370225.4
ABCA4	XM_047416704.1 linkuse as main transcript	c.4031+5G>T		splice_donor_5th_base_variant, intron_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
ABCA4	ENST00000370225.4 linkuse as main transcript	c.4253+5G>T		splice_donor_5th_base_variant, intron_variant		1	NM_000350.3	P1

Frequencies

GnomAD3 genomes

AF:

0.0000131

AC:

AN:

152122

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:

0.0000147

Gnomad OTH

AF:

0.00

GnomAD4 exome

AF:

0.0000103

AC:

AN:

1461674

Hom.:

Cov.:

AF XY:

0.0000124

AC XY:

AN XY:

727140

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:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000126

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000131

AC:

AN:

152122

Hom.:

Cov.:

AF XY:

0.0000135

AC XY:

AN XY:

74312

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:

0.0000147

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.00000378

EpiCase

AF:

0.0000545

EpiControl

AF:

0.00

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:5Other:1

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not provided

Pathogenic:2Other:1

Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Sep 12, 2022	Published functional studies demonstrate significant aberrant splicing with skipping of exon 28 (Sangermano et al., 2018); Not observed at significant frequency in large population cohorts (gnomAD); In-silico analysis is inconclusive as to whether the variant alters gene splicing. In the absence of RNA/functional studies, the actual effect of this sequence change is unknown.; This variant is associated with the following publications: (PMID: 25525159, 22247458, 9666097, 9973280, 23499370, 24550365, 28041643, 29162642, 32581362) -
not provided, no classification provided	literature only	Retina International	-	- -
Pathogenic, criteria provided, single submitter	clinical testing	Invitae	Jan 29, 2024	This sequence change falls in intron 28 of the ABCA4 gene. It does not directly change the encoded amino acid sequence of the ABCA4 protein. It affects a nucleotide within the consensus splice site. This variant is present in population databases (rs61750138, gnomAD 0.0009%). This variant has been observed in individuals with Stargardt disease (PMID: 9973280, 28041643; Invitae). ClinVar contains an entry for this variant (Variation ID: 99267). Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Studies have shown that this variant alters mRNA splicing and is expected to lead to the loss of protein expression (PMID: 29162642). This variant disrupts the c.4253+5G nucleotide in the ABCA4 gene. Other variant(s) that disrupt this nucleotide have been determined to be pathogenic (PMID: 10958763, 11385708, 28041643, 29162642). This suggests that this nucleotide is clinically significant, and that variants that disrupt this position are likely to be disease-causing. For these reasons, this variant has been classified as Pathogenic. -

ABCA4-related disorder

Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

PreventionGenetics, part of Exact Sciences

Dec 11, 2023

The ABCA4 c.4253+5G>T variant is predicted to interfere with splicing. This variant has been reported in individuals with Stargardt disease (Lewis et al. 1999. PubMed ID: 9973280; Supplemental data, Turro et al. 2020. PubMed ID: 32581362; Table S3, Suga et al. 2022. PubMed ID: 36284460). A functional study using a midigene splicing assay showed that this variant causes a significant decrease in correctly spliced mRNA (Sangermano et al. 2018. PubMed ID: 29162642). Alternate variants of this nucleotide and an adjacent nucleotide (c.4253+5G>A and c.4253+4C>T) have been reported in individuals with Stargardt disease (Rivera et al. 2000. PubMed ID: 10958763; Ozgul et al. 2004. PubMed ID: 15108289). This c.4253+5G>T variant has not been reported in a large population database, indicating this variant is rare. Given the evidence, we interpret this variant as pathogenic. -

Severe early-childhood-onset retinal dystrophy

Pathogenic:1

Likely pathogenic, no assertion criteria provided

research

NIHR Bioresource Rare Diseases, University of Cambridge

Jan 01, 2015

- -

Retinal dystrophy

Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Blueprint Genetics

Sep 06, 2018

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_noAF

Benign

-0.65

Cadd

Benign

3.2

Dann

Benign

0.81

Splicing

Name

Calibrated prediction

Score

Prediction

dbscSNV1_ADA

Pathogenic

1.0

dbscSNV1_RF

Pathogenic

0.84

SpliceAI score (max)

0.44

Details are displayed if max score is > 0.2

DS_DL_spliceai

0.44

Position offset: 5

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