rs142726108

Variant summary

Our verdict is Benign. The variant received -16 ACMG points: 0P and 16B. BP4_StrongBP6_Very_StrongBS2

The NM_001379500.1(COL18A1):​c.1675-6G>A variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0025 in 1,614,160 control chromosomes in the GnomAD database, including 18 homozygotes. In-silico tool predicts a benign outcome for this variant. 1/1 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Likely benign (★★).

Frequency

Genomes: 𝑓 0.0027 ( 6 hom., cov: 33)
Exomes 𝑓: 0.0025 ( 12 hom. )

Consequence

COL18A1
NM_001379500.1 splice_region, intron

Scores

2

Clinical Significance

Benign/Likely benign criteria provided, multiple submitters, no conflicts B:9

Conservation

PhyloP100: 0.583

Publications

0 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: ClinGen, G2P, Labcorp Genetics (formerly Invitae)
  • 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 -16 ACMG points.

BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.86).
BP6
Variant 21-45482789-G-A is Benign according to our data. Variant chr21-45482789-G-A is described in ClinVar as Benign/Likely_benign. ClinVar VariationId is 261893.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
BS2
High Homozygotes in GnomAd4 at 6 AD,AR gene

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001379500.1. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
COL18A1
NM_001379500.1
MANE Select
c.1675-6G>A
splice_region intron
N/ANP_001366429.1P39060-2
COL18A1
NM_130444.3
c.2920-6G>A
splice_region intron
N/ANP_569711.2
COL18A1
NM_030582.4
c.2215-6G>A
splice_region intron
N/ANP_085059.2A0AAG2UXZ5

Ensembl Transcripts

Sel.
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
COL18A1
ENST00000651438.1
MANE Select
c.1675-6G>A
splice_region intron
N/AENSP00000498485.1P39060-2
COL18A1
ENST00000355480.10
TSL:1
c.2215-6G>A
splice_region intron
N/AENSP00000347665.5P39060-1
COL18A1
ENST00000359759.8
TSL:5
c.2920-6G>A
splice_region intron
N/AENSP00000352798.4P39060-3

Frequencies

GnomAD3 genomes
AF:
0.00271
AC:
412
AN:
152160
Hom.:
6
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.000435
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00851
Gnomad ASJ
AF:
0.00979
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00228
Gnomad FIN
AF:
0.000565
Gnomad MID
AF:
0.0253
Gnomad NFE
AF:
0.00294
Gnomad OTH
AF:
0.00239
GnomAD2 exomes
AF:
0.00311
AC:
777
AN:
249542
AF XY:
0.00321
show subpopulations
Gnomad AFR exome
AF:
0.000517
Gnomad AMR exome
AF:
0.00501
Gnomad ASJ exome
AF:
0.0127
Gnomad EAS exome
AF:
0.0000556
Gnomad FIN exome
AF:
0.000557
Gnomad NFE exome
AF:
0.00343
Gnomad OTH exome
AF:
0.00478
GnomAD4 exome
AF:
0.00247
AC:
3618
AN:
1461882
Hom.:
12
Cov.:
31
AF XY:
0.00260
AC XY:
1892
AN XY:
727244
show subpopulations
African (AFR)
AF:
0.000627
AC:
21
AN:
33480
American (AMR)
AF:
0.00456
AC:
204
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.0120
AC:
314
AN:
26136
East Asian (EAS)
AF:
0.0000756
AC:
3
AN:
39700
South Asian (SAS)
AF:
0.00139
AC:
120
AN:
86258
European-Finnish (FIN)
AF:
0.000674
AC:
36
AN:
53418
Middle Eastern (MID)
AF:
0.0109
AC:
63
AN:
5768
European-Non Finnish (NFE)
AF:
0.00239
AC:
2659
AN:
1112002
Other (OTH)
AF:
0.00328
AC:
198
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.458
Heterozygous variant carriers
0
213
426
638
851
1064
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
Variant carriers
0
94
188
282
376
470
<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:
0.00271
AC:
412
AN:
152278
Hom.:
6
Cov.:
33
AF XY:
0.00285
AC XY:
212
AN XY:
74460
show subpopulations
African (AFR)
AF:
0.000433
AC:
18
AN:
41538
American (AMR)
AF:
0.00850
AC:
130
AN:
15298
Ashkenazi Jewish (ASJ)
AF:
0.00979
AC:
34
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5174
South Asian (SAS)
AF:
0.00228
AC:
11
AN:
4828
European-Finnish (FIN)
AF:
0.000565
AC:
6
AN:
10616
Middle Eastern (MID)
AF:
0.0272
AC:
8
AN:
294
European-Non Finnish (NFE)
AF:
0.00294
AC:
200
AN:
68032
Other (OTH)
AF:
0.00237
AC:
5
AN:
2114
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.492
Heterozygous variant carriers
0
19
37
56
74
93
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:
0.00315
Hom.:
1
Bravo
AF:
0.00290
Asia WGS
AF:
0.000289
AC:
1
AN:
3478
EpiCase
AF:
0.00540
EpiControl
AF:
0.00421

ClinVar

ClinVar submissions
Significance:Benign/Likely benign
Revision:criteria provided, multiple submitters, no conflicts
View on ClinVar
Pathogenic
VUS
Benign
Condition
-
-
4
not provided (4)
-
-
3
not specified (3)
-
-
1
Inborn genetic diseases (1)
-
-
1
Knobloch syndrome (1)

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.86
CADD
Benign
2.0
DANN
Benign
0.44
PhyloP100
0.58
Mutation Taster
=99/1
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.010
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: rs142726108; hg19: chr21-46902703; COSMIC: COSV62699489; COSMIC: COSV62699489; API