rs61751395

Variant names:

• chr1-94056683-A-T
• rs61751395
• NM_000350.3:c.2300T>A

Variant summary

Our verdict is Pathogenic. The variant received 19 ACMG points: 19P and 0B. PS3 PM1 PP2 PP3_Strong PP5_Very_Strong

The NM_000350.3(ABCA4):​c.2300T>A​(p.Val767Asp) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000112 in 1,614,034 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 (★★). ClinVar reports functional evidence for this variant: "SCV000511885: Published functional studies demonstrate a damaging effect (severe reduction in protein expression) (Shroyer et al., 2001)" and additional evidence is available in ClinVar. The gene ABCA4 is included in the ClinGen Criteria Specification Registry.

• Frequency:
  • Genomes: 𝑓 0.000033 (0 hom., cov: 33)
  • Exomes 𝑓: 0.0000089 (0 hom.)
• Consequence: ABCA4 NM_000350.3 missense
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:9 O:1
• Conservation: PhyloP100: 9.32
• Publications: 22 publications found

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
• age related macular degeneration 2

  Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

ACMG classification

Specifications for ABCA4 are available in the ClinGen Criteria Specification Registry and recommended for reference when assigning criteria.

Our verdict: Pathogenic. The variant received 19 ACMG points.

• PS3: PS3 evidence extracted from ClinVar submissions: SCV000511885: Published functional studies demonstrate a damaging effect (severe reduction in protein expression) (Shroyer et al., 2001); PMID:12442277; SCV001227097: Experimental studies have shown that this missense change affects ABCA4 function (PMID: 11687513).; SCV005351001: Functional studies have demonstrated that the variant reduces protein expression (Shroyer et al. 2001. PubMed ID: 11687513).; SCV006073024: Experimental studies have shown that this missense change affects ABCA4 function (Shroyer_2001). PMID:11687513
• PM1: In a hotspot region, there are 12 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 7 uncertain in NM_000350.3
• PP2: Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 578 curated pathogenic missense variants (we use a threshold of 10). The gene has 28 curated benign missense variants. Gene score misZ: -0.65813 (below the threshold of 3.09). Trascript score misZ: 1.3628 (below the threshold of 3.09). GenCC associations: The gene is linked to severe early-childhood-onset retinal dystrophy, retinitis pigmentosa, age related macular degeneration 2, retinitis pigmentosa 19, cone-rod dystrophy 3, ABCA4-related retinopathy, Stargardt disease, cone-rod dystrophy.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.98
• PP5: Variant 1-94056683-A-T is Pathogenic according to our data. Variant chr1-94056683-A-T is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 99127.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

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ABCA4	NM_000350.3	MANE Select	c.2300T>A	p.Val767Asp	missense	Exon 15 of 50	NP_000341.2	P78363
	ABCA4	NM_001425324.1		c.2161-1368T>A		intron	N/A	NP_001412253.1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ABCA4	ENST00000370225.4	TSL:1 MANE Select	c.2300T>A	p.Val767Asp	missense	Exon 15 of 50	ENSP00000359245.3	P78363
	ABCA4	ENST00000649773.1		c.2161-1368T>A		intron	N/A	ENSP00000496882.1	A0A3B3IRV8

Frequencies

GnomAD3 genomes AF: 0.0000329 AC: 5 AN: 152200 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.00

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: 0.0000735

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.0000199 AC: 5 AN: 251114 AF XY: 0.0000368

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000441

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000889 AC: 13 AN: 1461834 Hom.: 0 Cov.: 32 AF XY: 0.0000151 AC XY: 11 AN XY: 727214

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44722

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39698

South Asian (SAS) AF: 0.00 AC: 0 AN: 86238

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53414

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5746

European-Non Finnish (NFE) AF: 0.0000117 AC: 13 AN: 1112004

Other (OTH) AF: 0.00 AC: 0 AN: 60396

GnomAD4 genome AF: 0.0000329 AC: 5 AN: 152200 Hom.: 0 Cov.: 33 AF XY: 0.0000404 AC XY: 3 AN XY: 74342

African (AFR) AF: 0.00 AC: 0 AN: 41460

American (AMR) AF: 0.00 AC: 0 AN: 15276

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3472

East Asian (EAS) AF: 0.00 AC: 0 AN: 5198

South Asian (SAS) AF: 0.00 AC: 0 AN: 4826

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10626

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.0000735 AC: 5 AN: 68024

Other (OTH) AF: 0.00 AC: 0 AN: 2090

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.0000189

ExAC AF: 0.00000824 AC: 1

ClinVar

ClinVar submissions

Significance: Pathogenic/Likely pathogenic

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
3	-	-	not provided (4)
2	-	-	Retinal dystrophy (2)
2	-	-	Severe early-childhood-onset retinal dystrophy (2)
1	-	-	ABCA4-related disorder (1)
1	-	-	Retinitis pigmentosa (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.73
BayesDel_addAF	Pathogenic	0.33	D
BayesDel_noAF	Pathogenic	0.36
CADD	Uncertain	25
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.90	D
Eigen	Uncertain	0.35
Eigen_PC	Uncertain	0.48
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.97	D
M_CAP	Pathogenic	0.50	D
MetaRNN	Pathogenic	0.98	D
MetaSVM	Uncertain	-0.018	T
MutationAssessor	Uncertain	2.3	M
PhyloP100		9.3
PrimateAI	Uncertain	0.52	T
PROVEAN	Pathogenic	-5.4	D
REVEL	Pathogenic	0.87
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0010	D
Polyphen		0.059	B
Vest4		0.97
MutPred		0.86		Gain of helix (P = 0.1736)
MVP		0.87
MPC		0.50
ClinPred		0.98	D
GERP RS		5.7
Varity_R		0.97
gMVP		0.93
Mutation Taster		=4/96	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs61751395; hg19: chr1-94522239;