rs753824908

Variant names:

Variant summary

Our verdict is Pathogenic. The variant received 16 ACMG points: 16P and 0B. PVS1PP5_Very_Strong

The NM_001379500.1(COL18A1):c.2743C>T(p.Arg915*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000621 in 1,611,410 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 (★★). Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)

Exomes 𝑓: 0.0000062 ( 0 hom. )

Consequence

COL18A1
NM_001379500.1 stop_gained

Scores

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:5

Conservation

PhyloP100: -0.448

Publications

1 publications found

Variant links:

Genes affected

COL18A1 (HGNC:2195): (collagen type XVIII alpha 1 chain) This gene encodes the alpha chain of type XVIII collagen. This collagen is one of the multiplexins, extracellular matrix proteins that contain multiple triple-helix domains (collagenous domains) interrupted by non-collagenous domains. A long isoform of the protein has an N-terminal domain that is homologous to the extracellular part of frizzled receptors. Proteolytic processing at several endogenous cleavage sites in the C-terminal domain results in production of endostatin, a potent antiangiogenic protein that is able to inhibit angiogenesis and tumor growth. Mutations in this gene are associated with Knobloch syndrome. The main features of this syndrome involve retinal abnormalities, so type XVIII collagen may play an important role in retinal structure and in neural tube closure. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Dec 2014]

COL18A1 links:

SLC19A1 (HGNC:10937): (solute carrier family 19 member 1) The membrane protein encoded by this gene is a transporter of folate and is involved in the regulation of intracellular concentrations of folate. Three transcript variants encoding different isoforms have been found for this gene.[provided by RefSeq, Mar 2011]

SLC19A1 links:

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 16 ACMG points.

PVS1

Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.

PP5

Variant 21-45504431-C-T is Pathogenic according to our data. Variant chr21-45504431-C-T is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 191317.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
COL18A1	NM_001379500.1 link	c.2743C>T	p.Arg915*	stop_gained	Exon 34 of 42	ENST00000651438.1	NP_001366429.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
COL18A1	ENST00000651438.1 link	c.2743C>T	p.Arg915*	stop_gained	Exon 34 of 42		NM_001379500.1	ENSP00000498485.1		P39060-2

Frequencies

GnomAD3 genomes

AF:

0.00000658

AC:

AN:

152082

Hom.:

Cov.:

show subpopulations

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:

0.0000147

Gnomad OTH

AF:

0.00

GnomAD2 exomes

AF:

0.00000414

AC:

AN:

241808

AF XY:

0.00

show subpopulations

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:

0.00000923

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000617

AC:

AN:

1459328

Hom.:

Cov.:

AF XY:

0.00000964

AC XY:

AN XY:

725962

show subpopulations

African (AFR)

AF:

0.00

AC:

AN:

33446

American (AMR)

AF:

0.00

AC:

AN:

44626

Ashkenazi Jewish (ASJ)

AF:

0.0000384

AC:

AN:

26056

East Asian (EAS)

AF:

0.0000252

AC:

AN:

39686

South Asian (SAS)

AF:

0.0000116

AC:

AN:

86146

European-Finnish (FIN)

AF:

0.0000192

AC:

AN:

52050

Middle Eastern (MID)

AF:

0.00

AC:

AN:

5678

European-Non Finnish (NFE)

AF:

0.00000360

AC:

AN:

1111332

Other (OTH)

AF:

0.0000166

AC:

AN:

60308

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.453

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Exome Het

Variant carriers

<30

30-35

35-40

40-45

45-50

50-55

55-60

60-65

65-70

70-75

75-80

>80

Age

GnomAD4 genome

AF:

0.00000658

AC:

AN:

152082

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74284

show subpopulations

African (AFR)

AF:

0.00

AC:

AN:

41416

American (AMR)

AF:

0.00

AC:

AN:

15272

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

3472

East Asian (EAS)

AF:

0.00

AC:

AN:

5172

South Asian (SAS)

AF:

0.00

AC:

AN:

4826

European-Finnish (FIN)

AF:

0.00

AC:

AN:

10612

Middle Eastern (MID)

AF:

0.00

AC:

AN:

316

European-Non Finnish (NFE)

AF:

0.0000147

AC:

AN:

67994

Other (OTH)

AF:

0.00

AC:

AN:

2090

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.525

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Genome Het

Variant carriers

<30

30-35

35-40

40-45

45-50

50-55

55-60

60-65

65-70

70-75

75-80

>80

Age

ExAC

AF:

0.00000838

AC:

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:5

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not provided

Pathogenic:4

Sep 05, 2019

Revvity Omics, Revvity

Significance:Pathogenic

Review Status:criteria provided, single submitter

Collection Method:clinical testing

- -

Jan 01, 2022

CeGaT Center for Human Genetics Tuebingen

Significance:Pathogenic

Review Status:criteria provided, single submitter

Collection Method:clinical testing

- -

Genomic Medicine Center of Excellence, King Faisal Specialist Hospital and Research Centre

Significance:Likely pathogenic

Review Status:criteria provided, single submitter

Collection Method:research

- -

Dec 16, 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.Arg915*) in the COL18A1 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in COL18A1 are known to be pathogenic (PMID: 12415512, 25456301). This variant is not present in population databases (gnomAD no frequency). This premature translational stop signal has been observed in individual(s) with Knobloch syndrome (PMID: 21862674). ClinVar contains an entry for this variant (Variation ID: 191317). For these reasons, this variant has been classified as Pathogenic. -

Knobloch syndrome 1

Pathogenic:1

Juno Genomics, Hangzhou Juno Genomics, Inc

Significance:Pathogenic

Review Status:criteria provided, single submitter

Collection Method:clinical testing

PVS1+PM2_Supporting+PM3+PP4 -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_addAF

Pathogenic

0.63

BayesDel_noAF

Pathogenic

0.28

CADD

Pathogenic

(source)

DANN

Uncertain

0.99

Eigen

Benign

-0.12

Eigen_PC

Benign

-0.44

FATHMM_MKL

Benign

0.080

PhyloP100

-0.45

Vest4

0.83

GERP RS

2.2

RBP_binding_hub_radar

1.0

RBP_regulation_power_radar

2.8

Mutation Taster

=9/191

disease causing (ClinVar)

(source)

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.13

Details are displayed if max score is > 0.2

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

Publications

You must be logged in to view publications. This limit was set because tens of millions (!) of queries from AI bots are generated daily.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

Publications

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

Age Distribution

Age Distribution

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

Other links and lift over