rs61750564

chr1-94019691-C-Achr1-94019691-C-T

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PM1 PM2 PM5 PP3_Moderate

The NM_000350.3(ABCA4):c.5087G>T(p.Ser1696Ile) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,484 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. S1696R) has been classified as Likely pathogenic.

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: ABCA4 NM_000350.3 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 7.85

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]

ACMG classification

Verdict is Likely_pathogenic. Variant got 8 ACMG points.

• PM1: In a hotspot region, there are 5 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 3 uncertain in NM_000350.3
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr1-94019691-C-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 99344.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.933

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
ABCA4	NM_000350.3	c.5087G>T	p.Ser1696Ile	missense_variant	36/50	ENST00000370225.4
ABCA4	XM_047416704.1	c.4865G>T	p.Ser1622Ile	missense_variant	35/49

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
ABCA4	ENST00000370225.4	c.5087G>T	p.Ser1696Ile	missense_variant	36/50	1	NM_000350.3	P1
ABCA4	ENST00000460514.1	n.581G>T		non_coding_transcript_exon_variant	7/7	5
ABCA4	ENST00000470771.1	n.197G>T		non_coding_transcript_exon_variant	2/2	3

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD3 exomes AF: 0.00000399 AC: 1 AN: 250460 Hom.: 0 AF XY: 0.00000739 AC XY: 1 AN XY: 135352

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 SAS exome AF: 0.0000328

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461484 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 726974

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000116

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 31

ExAC AF: 0.00000824 AC: 1

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.81
BayesDel_addAF	Pathogenic	0.37	D
BayesDel_noAF	Pathogenic	0.39
Cadd	Pathogenic	26
Dann	Uncertain	1.0
DEOGEN2	Uncertain	0.71	D;D
Eigen	Pathogenic	0.94
Eigen_PC	Pathogenic	0.89
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Pathogenic	0.99	D;D
M_CAP	Pathogenic	0.88	D
MetaRNN	Pathogenic	0.93	D;D
MetaSVM	Uncertain	0.59	D
MutationTaster	Benign	1.0	D
PrimateAI	Uncertain	0.72	T
Sift4G	Pathogenic	0.0	D;D
Polyphen		1.0	.;D
Vest4		0.96
MutPred		0.63		.;Gain of catalytic residue at L1701 (P = 0.0448);
MVP		0.99
MPC		0.49
ClinPred		1.0	D
GERP RS		5.4
Varity_R		0.96
gMVP		0.93

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.060		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: rs61750564; hg19: chr1-94485247;