1-94121045-T-C

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1PS1_ModeratePP5_Very_Strong

The NM_000350.3(ABCA4):​c.1A>G​(p.Met1?) variant causes a start lost change. The variant allele was found at a frequency of 0.00000496 in 1,613,996 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 (★★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 31)
Exomes 𝑓: 0.0000048 ( 0 hom. )

Consequence

ABCA4
NM_000350.3 start_lost

Scores

6
8
1

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:6O:1

Conservation

PhyloP100: 4.87

Publications

22 publications found
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 Gene-Disease associations (from GenCC):
  • ABCA4-related retinopathy
    Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
  • cone-rod dystrophy 3
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P, Ambry Genetics
  • severe early-childhood-onset retinal dystrophy
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Laboratory for Molecular Medicine, Labcorp Genetics (formerly Invitae), Ambry Genetics
  • retinitis pigmentosa 19
    Inheritance: AR Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
  • cone-rod dystrophy
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • retinitis pigmentosa
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • Stargardt disease
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 18 ACMG points.

PVS1
Start lost variant, next in-frame start position is after 39 pathogenic variants. Next in-frame start position is after 61 codons. Genomic position: 94111559. Lost 0.027 part of the original CDS.
PS1
Another start lost variant in NM_000350.3 (ABCA4) was described as [Likely_pathogenic] in ClinVar
PP5
Variant 1-94121045-T-C is Pathogenic according to our data. Variant chr1-94121045-T-C is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 99110.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000350.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
ABCA4
NM_000350.3
MANE Select
c.1A>Gp.Met1?
start_lost
Exon 1 of 50NP_000341.2
ABCA4
NM_001425324.1
c.1A>Gp.Met1?
start_lost
Exon 1 of 49NP_001412253.1

Ensembl Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
ABCA4
ENST00000370225.4
TSL:1 MANE Select
c.1A>Gp.Met1?
start_lost
Exon 1 of 50ENSP00000359245.3
ABCA4
ENST00000649773.1
c.1A>Gp.Met1?
start_lost
Exon 1 of 19ENSP00000496882.1

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152110
Hom.:
0
Cov.:
31
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.000288
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000795
AC:
2
AN:
251478
AF XY:
0.00000736
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.0000992
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.000163
GnomAD4 exome
AF:
0.00000479
AC:
7
AN:
1461886
Hom.:
0
Cov.:
33
AF XY:
0.00000275
AC XY:
2
AN XY:
727244
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.0000224
AC:
1
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.0000765
AC:
2
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53416
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000270
AC:
3
AN:
1112008
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.461
Heterozygous variant carriers
0
1
2
2
3
4
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152110
Hom.:
0
Cov.:
31
AF XY:
0.0000135
AC XY:
1
AN XY:
74296
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41402
American (AMR)
AF:
0.00
AC:
0
AN:
15272
Ashkenazi Jewish (ASJ)
AF:
0.000288
AC:
1
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5186
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4826
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10606
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68028
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.0000364
Hom.:
0
Bravo
AF:
0.00000756
TwinsUK
AF:
0.00
AC:
0
ALSPAC
AF:
0.000259
AC:
1

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:6Other:1
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Pathogenic:2Other:1
Oct 20, 2021
GeneDx
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Identified in other unrelated patients with ABCA4-related disorders in published literature (Briggs et al., 2001; Maia-Lopes et al., 2009); Initiation codon variant in a gene for which loss-of-function is a known mechanism of disease; This variant is associated with the following publications: (PMID: 19365591, 28118664, 11527935, 24265693, 29925512, 31456290)

Retina International
Significance:not provided
Review Status:no classification provided
Collection Method:literature only

Jan 08, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change affects the initiator methionine of the ABCA4 mRNA. The next in-frame methionine is located at codon 61. This variant is present in population databases (rs201738997, gnomAD 0.01%). Disruption of the initiator codon has been observed in individuals with Stargardt disease (PMID: 28118664, 29925512). ClinVar contains an entry for this variant (Variation ID: 99110). For these reasons, this variant has been classified as Pathogenic.

Severe early-childhood-onset retinal dystrophy Pathogenic:2
Jan 01, 2016
Institute of Human Genetics, Univ. Regensburg, Univ. Regensburg
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Jan 30, 2021
Institute of Medical Molecular Genetics, University of Zurich
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Abnormality of the eye Pathogenic:1
Jul 10, 2021
Kariminejad - Najmabadi Pathology & Genetics Center
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Retinal dystrophy Pathogenic:1
Jan 01, 2023
Institute of Human Genetics, Univ. Regensburg, Univ. Regensburg
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.28
D
BayesDel_noAF
Pathogenic
0.17
CADD
Benign
23
DANN
Uncertain
0.99
DEOGEN2
Uncertain
0.54
D
Eigen
Uncertain
0.46
Eigen_PC
Uncertain
0.41
FATHMM_MKL
Uncertain
0.96
D
LIST_S2
Uncertain
0.90
D
M_CAP
Pathogenic
0.86
D
MetaRNN
Pathogenic
0.81
D
MetaSVM
Benign
-0.59
T
PhyloP100
4.9
PROVEAN
Uncertain
-2.9
D
REVEL
Uncertain
0.49
Sift
Pathogenic
0.0
D
Sift4G
Pathogenic
0.0
D
Polyphen
0.98
D
Vest4
0.97
MVP
0.72
ClinPred
0.99
D
GERP RS
3.8
PromoterAI
0.018
Neutral
Varity_R
0.86
gMVP
0.77
Mutation Taster
=2/198
disease causing (ClinVar)

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

Other links and lift over

dbSNP: rs201738997; hg19: chr1-94586601; API