NM_201253.3:c.1431delG

Variant names:

• chr1-197421256-CG-C
• rs1553260321
• NM_201253.3:c.1431delG

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_201253.3(CRB1):​c.1431delG​(p.Ser478ProfsTer24) variant causes a frameshift change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000205 in 1,461,848 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★★). Synonymous variant affecting the same amino acid position (i.e. G477G) has been classified as Likely benign. Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: CRB1 NM_201253.3 frameshift
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:8
• Conservation: PhyloP100: 9.49
• Publications: 2 publications found

Genes affected

CRB1 (HGNC:2343): (crumbs cell polarity complex component 1) This gene encodes a protein which is similar to the Drosophila crumbs protein and localizes to the inner segment of mammalian photoreceptors. In Drosophila crumbs localizes to the stalk of the fly photoreceptor and may be a component of the molecular scaffold that controls proper development of polarity in the eye. Mutations in this gene are associated with a severe form of retinitis pigmentosa, RP12, and with Leber congenital amaurosis. Alternate splicing results in multiple transcript variants, some protein coding and some non-protein coding.[provided by RefSeq, Apr 2012]

CRB1 Gene-Disease associations (from GenCC):

• hereditary macular dystrophy

  Inheritance: AR Classification: DEFINITIVE Submitted by: G2P
• Leber congenital amaurosis 8

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), Laboratory for Molecular Medicine, G2P
• retinitis pigmentosa 12

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae)
• Leber congenital amaurosis

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• nanophthalmia

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• pigmented paravenous retinochoroidal atrophy

  Inheritance: AD Classification: SUPPORTIVE, LIMITED Submitted by: Orphanet, G2P
• retinitis pigmentosa

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

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

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 1-197421256-CG-C is Pathogenic according to our data. Variant chr1-197421256-CG-C is described in ClinVar as Pathogenic. ClinVar VariationId is 446253.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_201253.3. 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
	CRB1	NM_201253.3	MANE Select	c.1431delG	p.Ser478ProfsTer24	frameshift	Exon 6 of 12	NP_957705.1	P82279-1
	CRB1	NM_001257965.2		c.1224delG	p.Ser409ProfsTer24	frameshift	Exon 8 of 15	NP_001244894.1	F5H0L2
	CRB1	NM_001193640.2		c.1095delG	p.Ser366ProfsTer24	frameshift	Exon 4 of 10	NP_001180569.1	P82279-3

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CRB1	ENST00000367400.8	TSL:1 MANE Select	c.1431delG	p.Ser478ProfsTer24	frameshift	Exon 6 of 12	ENSP00000356370.3	P82279-1
	CRB1	ENST00000638467.1	TSL:1	c.1431delG	p.Ser478ProfsTer24	frameshift	Exon 6 of 11	ENSP00000491102.1	P82279-2
	CRB1	ENST00000367399.6	TSL:1	c.1095delG	p.Ser366ProfsTer24	frameshift	Exon 4 of 10	ENSP00000356369.2	P82279-3

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1461848 Hom.: 0 Cov.: 35 AF XY: 0.00000275 AC XY: 2 AN XY: 727216

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

American (AMR) AF: 0.00 AC: 0 AN: 44720

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26134

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: 53414

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00000270 AC: 3 AN: 1111978

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

GnomAD4 genome Cov.: 33

ClinVar

ClinVar submissions

Significance: Pathogenic

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
2	-	-	Leber congenital amaurosis 8 (2)
1	-	-	Leber congenital amaurosis (1)
1	-	-	Macular dystrophy (1)
1	-	-	Pigmented paravenous retinochoroidal atrophy (1)
1	-	-	Retinitis pigmentosa 12 (1)
1	-	-	Retinitis pigmentosa 12;C1868310:Pigmented paravenous retinochoroidal atrophy;C3151202:Leber congenital amaurosis 8 (1)
1	-	-	Retinitis pigmentosa 12;C3151202:Leber congenital amaurosis 8 (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
PhyloP100		9.5
Mutation Taster		=0/200	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

Other links and lift over

dbSNP: rs1553260321; hg19: chr1-197390386;