rs114139997

Variant summary

Our verdict is Benign. The variant received -20 ACMG points: 0P and 20B. BP4_StrongBP6_Very_StrongBS1BS2

The ENST00000355480.10(COL18A1):​c.331G>A​(p.Gly111Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000916 in 1,613,116 control chromosomes in the GnomAD database, including 11 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Benign (★★).

Frequency

Genomes: 𝑓 0.0051 ( 7 hom., cov: 33)
Exomes 𝑓: 0.00048 ( 4 hom. )

Consequence

COL18A1
ENST00000355480.10 missense

Scores

3
5
9

Clinical Significance

Benign criteria provided, multiple submitters, no conflicts B:4

Conservation

PhyloP100: 1.32

Publications

18 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 -20 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.010848165).
BP6
Variant 21-45455861-G-A is Benign according to our data. Variant chr21-45455861-G-A is described in ClinVar as Benign. ClinVar VariationId is 447126.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
BS1
Variant frequency is greater than expected in population afr. GnomAd4 allele frequency = 0.00507 (772/152264) while in subpopulation AFR AF = 0.018 (749/41544). AF 95% confidence interval is 0.017. There are 7 homozygotes in GnomAd4. There are 367 alleles in the male GnomAd4 subpopulation. Median coverage is 33. This position passed quality control check.
BS2
High Homozygotes in GnomAd4 at 7 AD,AR gene

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
COL18A1NM_001379500.1 linkc.107-12381G>A intron_variant Intron 2 of 41 ENST00000651438.1 NP_001366429.1
COL18A1NM_130444.3 linkc.331G>A p.Gly111Arg missense_variant Exon 1 of 41 NP_569711.2 P39060
COL18A1NM_030582.4 linkc.331G>A p.Gly111Arg missense_variant Exon 1 of 41 NP_085059.2 P39060D3DSM5

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
COL18A1ENST00000355480.10 linkc.331G>A p.Gly111Arg missense_variant Exon 1 of 41 1 ENSP00000347665.5 P39060-1
COL18A1ENST00000651438.1 linkc.107-12381G>A intron_variant Intron 2 of 41 NM_001379500.1 ENSP00000498485.1 P39060-2
COL18A1ENST00000359759.8 linkc.331G>A p.Gly111Arg missense_variant Exon 1 of 41 5 ENSP00000352798.4 P39060-3

Frequencies

GnomAD3 genomes
AF:
0.00507
AC:
772
AN:
152146
Hom.:
7
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0181
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00118
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.000207
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00144
GnomAD2 exomes
AF:
0.00123
AC:
304
AN:
247408
AF XY:
0.000913
show subpopulations
Gnomad AFR exome
AF:
0.0187
Gnomad AMR exome
AF:
0.000493
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000179
Gnomad OTH exome
AF:
0.000332
GnomAD4 exome
AF:
0.000483
AC:
705
AN:
1460852
Hom.:
4
Cov.:
72
AF XY:
0.000405
AC XY:
294
AN XY:
726752
show subpopulations
African (AFR)
AF:
0.0182
AC:
610
AN:
33480
American (AMR)
AF:
0.000514
AC:
23
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.0000232
AC:
2
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
52392
Middle Eastern (MID)
AF:
0.000693
AC:
4
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000126
AC:
14
AN:
1112006
Other (OTH)
AF:
0.000861
AC:
52
AN:
60388
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
59
118
178
237
296
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
Variant carriers
0
22
44
66
88
110
<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:
0.00507
AC:
772
AN:
152264
Hom.:
7
Cov.:
33
AF XY:
0.00493
AC XY:
367
AN XY:
74450
show subpopulations
African (AFR)
AF:
0.0180
AC:
749
AN:
41544
American (AMR)
AF:
0.00118
AC:
18
AN:
15306
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5176
South Asian (SAS)
AF:
0.000207
AC:
1
AN:
4822
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10622
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68006
Other (OTH)
AF:
0.00142
AC:
3
AN:
2112
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.498
Heterozygous variant carriers
0
41
81
122
162
203
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Genome Hom
Variant carriers
0
10
20
30
40
50
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.00203
Hom.:
2
Bravo
AF:
0.00574
ESP6500AA
AF:
0.0188
AC:
81
ESP6500EA
AF:
0.000118
AC:
1
ExAC
AF:
0.00167
AC:
202
Asia WGS
AF:
0.000866
AC:
3
AN:
3478
EpiCase
AF:
0.0000545
EpiControl
AF:
0.00

ClinVar

Significance: Benign
Submissions summary: Benign:4
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Benign:2
Jan 30, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

-
Breakthrough Genomics, Breakthrough Genomics
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:not provided

- -

not specified Benign:1
Sep 20, 2016
Athena Diagnostics
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

COL18A1-related disorder Benign:1
May 08, 2019
PreventionGenetics, part of Exact Sciences
Significance:Benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

This variant is classified as benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications). -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.57
BayesDel_addAF
Benign
-0.39
T
BayesDel_noAF
Benign
-0.32
CADD
Benign
17
DANN
Uncertain
1.0
DEOGEN2
Benign
0.14
.;T
Eigen
Uncertain
0.21
Eigen_PC
Benign
0.11
FATHMM_MKL
Benign
0.71
D
LIST_S2
Benign
0.73
T;T
MetaRNN
Benign
0.011
T;T
MetaSVM
Benign
-0.73
T
PhyloP100
1.3
PrimateAI
Uncertain
0.51
T
PROVEAN
Uncertain
-3.6
D;D
REVEL
Uncertain
0.35
Sift
Pathogenic
0.0
D;D
Sift4G
Pathogenic
0.0
D;D
Polyphen
0.97
D;D
Vest4
0.33
MutPred
0.84
Loss of helix (P = 0.0167);Loss of helix (P = 0.0167);
MVP
0.73
MPC
0.080
ClinPred
0.054
T
GERP RS
3.7
PromoterAI
0.0024
Neutral
Varity_R
0.55
gMVP
0.19
Mutation Taster
=98/2
polymorphism

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: rs114139997; hg19: chr21-46875775; API