rs61749440

Variant summary

Our verdict is Likely benign. Variant got -5 ACMG points: 0P and 5B. BP4_StrongBS2_Supporting

The NM_000350.3(ABCA4):​c.2690C>T​(p.Thr897Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00144 in 1,614,066 control chromosomes in the GnomAD database, including 7 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. T897T) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.0013 ( 1 hom., cov: 32)
Exomes 𝑓: 0.0015 ( 6 hom. )

Consequence

ABCA4
NM_000350.3 missense

Scores

1
8
10

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1U:6B:7O:1

Conservation

PhyloP100: 2.35
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -5 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.009508371).
BS2
High Homozygotes in GnomAdExome4 at 6 AD,AR geneVariant has number of homozygotes lower than other variant known as pathogenic in the gene, so the strength is limited to Supporting.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
ABCA4NM_000350.3 linkc.2690C>T p.Thr897Ile missense_variant Exon 18 of 50 ENST00000370225.4 NP_000341.2 P78363Q6AI28
ABCA4NM_001425324.1 linkc.2468C>T p.Thr823Ile missense_variant Exon 17 of 49 NP_001412253.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
ABCA4ENST00000370225.4 linkc.2690C>T p.Thr897Ile missense_variant Exon 18 of 50 1 NM_000350.3 ENSP00000359245.3 P78363
ABCA4ENST00000649773.1 linkc.2468C>T p.Thr823Ile missense_variant Exon 17 of 19 ENSP00000496882.1 A0A3B3IRV8

Frequencies

GnomAD3 genomes
AF:
0.00130
AC:
197
AN:
152070
Hom.:
1
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.000362
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00229
Gnomad ASJ
AF:
0.00576
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.000189
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00179
Gnomad OTH
AF:
0.00144
GnomAD3 exomes
AF:
0.00122
AC:
308
AN:
251454
Hom.:
3
AF XY:
0.00117
AC XY:
159
AN XY:
135906
show subpopulations
Gnomad AFR exome
AF:
0.000185
Gnomad AMR exome
AF:
0.00107
Gnomad ASJ exome
AF:
0.00417
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.000359
Gnomad FIN exome
AF:
0.000370
Gnomad NFE exome
AF:
0.00167
Gnomad OTH exome
AF:
0.00277
GnomAD4 exome
AF:
0.00146
AC:
2129
AN:
1461878
Hom.:
6
Cov.:
31
AF XY:
0.00146
AC XY:
1059
AN XY:
727240
show subpopulations
Gnomad4 AFR exome
AF:
0.000329
Gnomad4 AMR exome
AF:
0.000984
Gnomad4 ASJ exome
AF:
0.00566
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.000278
Gnomad4 FIN exome
AF:
0.000431
Gnomad4 NFE exome
AF:
0.00158
Gnomad4 OTH exome
AF:
0.00174
GnomAD4 genome
AF:
0.00129
AC:
197
AN:
152188
Hom.:
1
Cov.:
32
AF XY:
0.00106
AC XY:
79
AN XY:
74402
show subpopulations
Gnomad4 AFR
AF:
0.000361
Gnomad4 AMR
AF:
0.00229
Gnomad4 ASJ
AF:
0.00576
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.000189
Gnomad4 NFE
AF:
0.00179
Gnomad4 OTH
AF:
0.00142
Alfa
AF:
0.00184
Hom.:
2
Bravo
AF:
0.00123
TwinsUK
AF:
0.00216
AC:
8
ALSPAC
AF:
0.000519
AC:
2
ESP6500AA
AF:
0.000454
AC:
2
ESP6500EA
AF:
0.00140
AC:
12
ExAC
AF:
0.00114
AC:
138
EpiCase
AF:
0.00207
EpiControl
AF:
0.00207

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:1Uncertain:6Benign:7Other:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Pathogenic:1Uncertain:5Benign:1Other:1
-
Joint Genome Diagnostic Labs from Nijmegen and Maastricht, Radboudumc and MUMC+
Significance: Uncertain significance
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

Aug 01, 2019
CeGaT Center for Human Genetics Tuebingen
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

-
Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center
Significance: Uncertain significance
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

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

- -

Jan 27, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Likely benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Apr 05, 2019
GeneDx
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Reported previously in association with Stargardt disease and cone-rod dystrophy as heterozygous with other ABCA4 variants (Salles et al., 2018) as well as heterozygous without a second variant (Simonelli et al., 2000; Tsipi et al., 2016); In silico analysis, which includes protein predictors and evolutionary conservation, supports a deleterious effect; This variant is associated with the following publications: (PMID: 10711710, 11328725, 22995991, 27014590, 22264887, 21911583, 26103963, 30093795, 28118664, 29178665, 11702214, 29925512, 18161617) -

Sep 14, 2016
Eurofins Ntd Llc (ga)
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

-
Clinical Genetics, Academic Medical Center
Significance: Uncertain significance
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

Age related macular degeneration 2 Uncertain:1
Oct 11, 2018
Centre for Mendelian Genomics, University Medical Centre Ljubljana
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This variant was classified as: Uncertain significance. The available evidence favors the benign nature of this variant, however the evidence is insufficent to prove its benign nature. The following ACMG criteria were applied in classifying this variant: BP6. -

Retinitis Pigmentosa, Recessive Benign:1
Jun 14, 2016
Illumina Laboratory Services, Illumina
Significance: Likely benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Stargardt Disease, Recessive Benign:1
Jun 14, 2016
Illumina Laboratory Services, Illumina
Significance: Likely benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

ABCA4-related disorder Benign:1
Apr 27, 2017
Illumina Laboratory Services, Illumina
Significance: Likely benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

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). No publications were found based on this search. Allele frequency data from public databases allowed determination this variant is unlikely to cause disease. Therefore, this variant is classified as likely benign. -

Cone-Rod Dystrophy, Recessive Benign:1
Jun 14, 2016
Illumina Laboratory Services, Illumina
Significance: Likely benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Retinal dystrophy Benign:1
Jan 01, 2022
Institute of Human Genetics, Univ. Regensburg, Univ. Regensburg
Significance: Likely benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Macular degeneration Benign:1
Jun 14, 2016
Illumina Laboratory Services, Illumina
Significance: Likely benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.27
BayesDel_addAF
Uncertain
0.047
T
BayesDel_noAF
Pathogenic
0.29
CADD
Benign
21
DANN
Uncertain
0.99
DEOGEN2
Uncertain
0.45
T;.
Eigen
Uncertain
0.24
Eigen_PC
Uncertain
0.32
FATHMM_MKL
Benign
0.70
D
LIST_S2
Benign
0.73
T;T
M_CAP
Benign
0.027
D
MetaRNN
Benign
0.0095
T;T
MetaSVM
Uncertain
0.10
D
MutationAssessor
Benign
1.7
L;.
PrimateAI
Uncertain
0.63
T
PROVEAN
Benign
-1.7
N;.
REVEL
Uncertain
0.62
Sift
Benign
0.19
T;.
Sift4G
Benign
0.20
T;.
Polyphen
0.054
B;.
Vest4
0.80
MVP
0.94
MPC
0.30
ClinPred
0.022
T
GERP RS
5.3
Varity_R
0.11
gMVP
0.67

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.

Other links and lift over

dbSNP: rs61749440; hg19: chr1-94514477; API