rs187721798

Variant summary

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

The NM_001379500.1(COL18A1):​c.2782G>A​(p.Gly928Arg) variant causes a missense change. The variant allele was found at a frequency of 0.00144 in 1,607,030 control chromosomes in the GnomAD database, including 29 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Benign (★★). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Benign in ClinVar. Synonymous variant affecting the same amino acid position (i.e. G928G) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.0078 ( 16 hom., cov: 33)
Exomes 𝑓: 0.00078 ( 13 hom. )

Consequence

COL18A1
NM_001379500.1 missense

Scores

2
10
6

Clinical Significance

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

Conservation

PhyloP100: 4.95

Publications

3 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]
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]

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=0.007863849).
BP6
Variant 21-45504470-G-A is Benign according to our data. Variant chr21-45504470-G-A is described in ClinVar as Benign. ClinVar VariationId is 447120.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 = 0.00782 (1182/151120) while in subpopulation AFR AF = 0.0275 (1133/41150). AF 95% confidence interval is 0.0262. There are 16 homozygotes in GnomAd4. There are 534 alleles in the male GnomAd4 subpopulation. Median coverage is 33. This position passed quality control check.
BS2
High Homozygotes in GnomAd4 at 16 AD,AR gene

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
COL18A1NM_001379500.1 linkc.2782G>A p.Gly928Arg missense_variant Exon 34 of 42 ENST00000651438.1 NP_001366429.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
COL18A1ENST00000651438.1 linkc.2782G>A p.Gly928Arg missense_variant Exon 34 of 42 NM_001379500.1 ENSP00000498485.1 P39060-2

Frequencies

GnomAD3 genomes
AF:
0.00779
AC:
1177
AN:
151002
Hom.:
15
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0275
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00218
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:
0.0000738
Gnomad OTH
AF:
0.00532
GnomAD2 exomes
AF:
0.00179
AC:
426
AN:
237460
AF XY:
0.00139
show subpopulations
Gnomad AFR exome
AF:
0.0270
Gnomad AMR exome
AF:
0.00144
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000378
Gnomad OTH exome
AF:
0.000346
GnomAD4 exome
AF:
0.000780
AC:
1136
AN:
1455910
Hom.:
13
Cov.:
32
AF XY:
0.000675
AC XY:
489
AN XY:
724276
show subpopulations
African (AFR)
AF:
0.0271
AC:
906
AN:
33378
American (AMR)
AF:
0.00175
AC:
78
AN:
44598
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26056
East Asian (EAS)
AF:
0.0000504
AC:
2
AN:
39664
South Asian (SAS)
AF:
0.000163
AC:
14
AN:
86064
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
51806
Middle Eastern (MID)
AF:
0.000564
AC:
3
AN:
5316
European-Non Finnish (NFE)
AF:
0.0000550
AC:
61
AN:
1108994
Other (OTH)
AF:
0.00120
AC:
72
AN:
60034
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.505
Heterozygous variant carriers
0
62
123
185
246
308
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
Variant carriers
0
32
64
96
128
160
<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:
0.00782
AC:
1182
AN:
151120
Hom.:
16
Cov.:
33
AF XY:
0.00723
AC XY:
534
AN XY:
73856
show subpopulations
African (AFR)
AF:
0.0275
AC:
1133
AN:
41150
American (AMR)
AF:
0.00217
AC:
33
AN:
15178
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5040
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4780
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10510
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
292
European-Non Finnish (NFE)
AF:
0.0000739
AC:
5
AN:
67702
Other (OTH)
AF:
0.00526
AC:
11
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.508
Heterozygous variant carriers
0
57
114
172
229
286
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Genome Hom
Variant carriers
0
20
40
60
80
100
<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:
0.000645
Hom.:
7
Bravo
AF:
0.00869
ESP6500AA
AF:
0.0249
AC:
78
ESP6500EA
AF:
0.000136
AC:
1
ExAC
AF:
0.00204
AC:
239
EpiCase
AF:
0.000218
EpiControl
AF:
0.000119

ClinVar

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

Submissions by phenotype

not provided Benign:2
-
Breakthrough Genomics, Breakthrough Genomics
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:not provided

- -

Feb 03, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not specified Benign:1
Sep 19, 2016
Athena Diagnostics
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Knobloch syndrome Benign:1
Jan 13, 2018
Illumina Laboratory Services, Illumina
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.31
BayesDel_addAF
Benign
-0.082
T
BayesDel_noAF
Uncertain
0.13
CADD
Pathogenic
26
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.60
.;.;D;T
Eigen
Uncertain
0.48
Eigen_PC
Uncertain
0.27
FATHMM_MKL
Benign
0.68
D
LIST_S2
Benign
0.82
T;T;T;T
MetaRNN
Benign
0.0079
T;T;T;T
MetaSVM
Uncertain
0.66
D
MutationAssessor
Pathogenic
4.3
.;.;H;.
PhyloP100
4.9
PrimateAI
Uncertain
0.72
T
PROVEAN
Pathogenic
-5.0
D;D;D;D
REVEL
Uncertain
0.60
Sift
Uncertain
0.0030
D;D;D;D
Sift4G
Uncertain
0.0020
D;D;D;D
Polyphen
1.0
D;D;D;.
Vest4
0.75
MVP
0.97
MPC
0.44
ClinPred
0.061
T
GERP RS
4.5
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.24
gMVP
0.73
Mutation Taster
=84/16
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: rs187721798; hg19: chr21-46924384; API