chr8-95247686-C-T

Variant names:

• chr8-95247686-C-T
• rs748014296
• NM_177965.4:c.555G>A

Variant summary

Our verdict is Pathogenic. Variant got 14 ACMG points: 14P and 0B. PVS1_Strong PM2 PP5_Very_Strong

The NM_177965.4(CFAP418):​c.555G>A​(p.Trp185*) variant causes a stop gained change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000274 in 1,461,850 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: not found (cov: 32)
  • Exomes 𝑓: 0.0000027 (0 hom.)
• Consequence: CFAP418 NM_177965.4 stop_gained
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:3
• Conservation: PhyloP100: 7.24

Genes affected

CFAP418 (HGNC:27232): (cilia and flagella associated protein 418) This gene encodes a ubiquitously expressed protein of unknown function. It has high levels of mRNA expression in the brain, heart, and retina and the protein co-localizes with polyglutamylated tubulin at the base of the primary cilium in human retinal pigment epithelial cells. Mutations in this gene have been associated with autosomal recessive cone-rod dystrophy (arCRD) and retinitis pigmentosa (arRP). [provided by RefSeq, Mar 2012]

CFAP418-AS1 (HGNC:50444): (CFAP418 antisense RNA 1)

ACMG classification

Verdict is Pathogenic. Variant got 14 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. Fraction of 0.111 CDS is truncated, and there are 1 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 8-95247686-C-T is Pathogenic according to our data. Variant chr8-95247686-C-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 417788.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr8-95247686-C-T is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CFAP418	NM_177965.4	c.555G>A	p.Trp185*	stop_gained	Exon 6 of 6	ENST00000286688.6	NP_808880.1
CFAP418	NM_001363260.1	c.459G>A	p.Trp153*	stop_gained	Exon 5 of 5		NP_001350189.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CFAP418	ENST00000286688.6	c.555G>A	p.Trp185*	stop_gained	Exon 6 of 6	1	NM_177965.4	ENSP00000286688.5
CFAP418-AS1	ENST00000517655.1	n.521+42374C>T		intron_variant	Intron 2 of 2	4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000796 AC: 2 AN: 251368 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 135858

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: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000176

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000274 AC: 4 AN: 1461850 Hom.: 0 Cov.: 31 AF XY: 0.00000275 AC XY: 2 AN XY: 727238

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: 0.00000270

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

Alfa AF: 0.0000434 Hom.: 0

Bravo AF: 0.00000378

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Pathogenic:2

Dec 24, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change creates a premature translational stop signal (p.Trp185*) in the C8orf37 gene. While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 23 amino acid(s) of the C8orf37 protein. This variant is present in population databases (rs748014296, gnomAD 0.002%). This premature translational stop signal has been observed in individual(s) with clinical features of inherited retinal dystrophy (PMID: 25802487, 29843741). It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 417788). This variant disrupts a region of the C8orf37 protein in which other variant(s) (p.Trp202*) have been determined to be pathogenic (internal data). This suggests that this is a clinically significant region of the protein, and that variants that disrupt it are likely to be disease-causing. For these reasons, this variant has been classified as Pathogenic. -

Mar 10, 2023

GeneDx

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Nonsense variant in the C-terminus predicted to result in protein truncation, as the last 23 amino acids are lost, and other loss-of-function variants have been reported downstream in the Human Gene Mutation Database (HGMD); Not observed at a significant frequency in large population cohorts (gnomAD); This variant is associated with the following publications: (PMID: 25802487, 29843741, 31980526) -

Retinitis pigmentosa 64 Pathogenic:1

Mar 28, 2017

OMIM

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: literature only

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.61	D
BayesDel_noAF	Pathogenic	0.65
CADD	Pathogenic	40
DANN	Uncertain	1.0
Eigen	Pathogenic	0.94
Eigen_PC	Pathogenic	0.83
FATHMM_MKL	Pathogenic	0.98	D
Vest4		0.27
GERP RS		5.4

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

Other links and lift over

dbSNP: rs748014296; hg19: chr8-96259914;