21-45488441-T-G

Variant summary

Our verdict is Benign. The variant received -7 ACMG points: 0P and 7B. BP4_StrongBP6_ModerateBP7

The NM_001379500.1(COL18A1):​c.1920T>G​(p.Leu640Leu) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000411 in 1,461,574 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★). Synonymous variant affecting the same amino acid position (i.e. L640L) has been classified as Benign.

Frequency

Genomes: 𝑓 0.0 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000041 ( 1 hom. )
Failed GnomAD Quality Control

Consequence

COL18A1
NM_001379500.1 synonymous

Scores

2

Clinical Significance

Likely benign criteria provided, single submitter B:1

Conservation

PhyloP100: -0.0120

Publications

44 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 Gene-Disease associations (from GenCC):
  • Knobloch syndrome 1
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), ClinGen, G2P
  • Knobloch syndrome
    Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: Laboratory for Molecular Medicine, Orphanet
  • hereditary glaucoma, primary closed-angle
    Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Benign. The variant received -7 ACMG points.

BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.8).
BP6
Variant 21-45488441-T-G is Benign according to our data. Variant chr21-45488441-T-G is described in ClinVar as [Likely_benign]. Clinvar id is 1673079.Status of the report is criteria_provided_single_submitter, 1 stars.
BP7
Synonymous conserved (PhyloP=-0.012 with no splicing effect.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
COL18A1NM_001379500.1 linkc.1920T>G p.Leu640Leu synonymous_variant Exon 18 of 42 ENST00000651438.1 NP_001366429.1
COL18A1NM_130444.3 linkc.3165T>G p.Leu1055Leu synonymous_variant Exon 17 of 41 NP_569711.2 P39060
COL18A1NM_030582.4 linkc.2460T>G p.Leu820Leu synonymous_variant Exon 17 of 41 NP_085059.2 P39060D3DSM5

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
COL18A1ENST00000651438.1 linkc.1920T>G p.Leu640Leu synonymous_variant Exon 18 of 42 NM_001379500.1 ENSP00000498485.1 P39060-2
COL18A1ENST00000355480.10 linkc.2460T>G p.Leu820Leu synonymous_variant Exon 17 of 41 1 ENSP00000347665.5 P39060-1
COL18A1ENST00000359759.8 linkc.3165T>G p.Leu1055Leu synonymous_variant Exon 17 of 41 5 ENSP00000352798.4 P39060-3

Frequencies

GnomAD3 genomes
AF:
0.00
AC:
0
AN:
151996
Hom.:
0
Cov.:
32
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:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000803
AC:
2
AN:
249126
AF XY:
0.00
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000290
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.000165
GnomAD4 exome
AF:
0.00000411
AC:
6
AN:
1461574
Hom.:
1
Cov.:
49
AF XY:
0.00000413
AC XY:
3
AN XY:
727064
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.0000447
AC:
2
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26134
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39698
South Asian (SAS)
AF:
0.0000232
AC:
2
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53168
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
8.99e-7
AC:
1
AN:
1111970
Other (OTH)
AF:
0.00
AC:
0
AN:
60374
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<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
Data not reliable, filtered out with message: AC0
AF:
0.00
AC:
0
AN:
151996
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74230
African (AFR)
AF:
0.00
AC:
0
AN:
41380
American (AMR)
AF:
0.00
AC:
0
AN:
15278
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5156
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4826
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10584
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
67990
Other (OTH)
AF:
0.00
AC:
0
AN:
2088
Alfa
AF:
0.00
Hom.:
27466

ClinVar

Significance: Likely benign
Submissions summary: Benign:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

not provided Benign:1
Oct 15, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.80
CADD
Benign
4.3
DANN
Benign
0.50
PhyloP100
-0.012
RBP_binding_hub_radar
1.1
RBP_regulation_power_radar
2.4

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

Other links and lift over

dbSNP: rs11702425; hg19: chr21-46908355; API