NM_001846.4:c.4987G>A

Variant summary

Our verdict is Likely benign. The variant received -4 ACMG points: 1P and 5B. PP3BS1_SupportingBS2

The NM_001846.4(COL4A2):​c.4987G>A​(p.Gly1663Ser) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00072 in 1,613,506 control chromosomes in the GnomAD database, including 3 homozygotes. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. G1663G) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.00040 ( 0 hom., cov: 33)
Exomes 𝑓: 0.00075 ( 3 hom. )

Consequence

COL4A2
NM_001846.4 missense

Scores

15
3
1

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1U:2B:5

Conservation

PhyloP100: 9.54

Publications

7 publications found
Variant links:
Genes affected
COL4A2 (HGNC:2203): (collagen type IV alpha 2 chain) This gene encodes one of the six subunits of type IV collagen, the major structural component of basement membranes. The C-terminal portion of the protein, known as canstatin, is an inhibitor of angiogenesis and tumor growth. Like the other members of the type IV collagen gene family, this gene is organized in a head-to-head conformation with another type IV collagen gene so that each gene pair shares a common promoter. [provided by RefSeq, Jul 2008]
COL4A2 Gene-Disease associations (from GenCC):
  • porencephaly 2
    Inheritance: AD Classification: STRONG, MODERATE Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics, G2P
  • COL4A1 or COL4A2-related cerebral small vessel disease
    Inheritance: AD Classification: MODERATE Submitted by: Illumina
  • familial porencephaly
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -4 ACMG points.

PP3
MetaRNN computational evidence supports a deleterious effect, 0.815
BS1
Variant frequency is greater than expected in population nfe. GnomAd4 allele frequency = 0.000401 (61/152292) while in subpopulation NFE AF = 0.000838 (57/68022). AF 95% confidence interval is 0.000664. There are 0 homozygotes in GnomAd4. There are 23 alleles in the male GnomAd4 subpopulation. Median coverage is 33. This position passed quality control check. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting
BS2
High AC in GnomAd4 at 61 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
COL4A2NM_001846.4 linkc.4987G>A p.Gly1663Ser missense_variant Exon 48 of 48 ENST00000360467.7 NP_001837.2 P08572A0A024RDW8

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
COL4A2ENST00000360467.7 linkc.4987G>A p.Gly1663Ser missense_variant Exon 48 of 48 5 NM_001846.4 ENSP00000353654.5 P08572

Frequencies

GnomAD3 genomes
AF:
0.000401
AC:
61
AN:
152174
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000482
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000655
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:
0.000838
Gnomad OTH
AF:
0.000478
GnomAD2 exomes
AF:
0.000498
AC:
124
AN:
248916
AF XY:
0.000518
show subpopulations
Gnomad AFR exome
AF:
0.0000649
Gnomad AMR exome
AF:
0.0000579
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.000139
Gnomad NFE exome
AF:
0.00104
Gnomad OTH exome
AF:
0.000165
GnomAD4 exome
AF:
0.000753
AC:
1100
AN:
1461214
Hom.:
3
Cov.:
34
AF XY:
0.000730
AC XY:
531
AN XY:
726936
show subpopulations
African (AFR)
AF:
0.000299
AC:
10
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:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86258
European-Finnish (FIN)
AF:
0.0000379
AC:
2
AN:
52748
Middle Eastern (MID)
AF:
0.000867
AC:
5
AN:
5768
European-Non Finnish (NFE)
AF:
0.000938
AC:
1043
AN:
1112010
Other (OTH)
AF:
0.000613
AC:
37
AN:
60392
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.477
Heterozygous variant carriers
0
80
159
239
318
398
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
Variant carriers
0
36
72
108
144
180
<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:
0.000401
AC:
61
AN:
152292
Hom.:
0
Cov.:
33
AF XY:
0.000309
AC XY:
23
AN XY:
74456
show subpopulations
African (AFR)
AF:
0.0000481
AC:
2
AN:
41574
American (AMR)
AF:
0.0000654
AC:
1
AN:
15296
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5176
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4826
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10610
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.000838
AC:
57
AN:
68022
Other (OTH)
AF:
0.000473
AC:
1
AN:
2112
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.502
Heterozygous variant carriers
0
4
8
11
15
19
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome 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
Alfa
AF:
0.000914
Hom.:
1
Bravo
AF:
0.000431
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.00118
AC:
10
ExAC
AF:
0.000595
AC:
72
EpiCase
AF:
0.000818
EpiControl
AF:
0.00107

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:1Uncertain:2Benign:5
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not specified Uncertain:1Benign:1
May 04, 2022
Mendelics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Nov 17, 2023
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: COL4A2 c.4987G>A (p.Gly1663Ser) results in a non-conservative amino acid change located in the collagen IV, non-collagenous domain (IPR001442) of the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 0.00072 in 1613506 control chromosomes (i.e. over 1100 individuals), including 3 homozygotes, and found predominantly at a frequency of 0.00093 within the Non-Finnish European subpopulation in the gnomAD database (v4.0). This data strongly suggests the variant is unlikely to be associated with a penetrant autosomal dominant condition and is instead a benign polymorphism found primarily in individuals of Non-Finish European ancestry. To our knowledge, no occurrence of c.4987G>A in individuals affected with Porencephaly 2 and no experimental evidence demonstrating its impact on protein function have been reported. Six submitters have cited clinical-significance assessments for this variant to ClinVar after 2014. Four submitters classified the variant as benign/likely benign and two classified it as uncertain significance. Based on the evidence outlined above, the variant was classified as benign. -

not provided Uncertain:1Benign:1
Oct 01, 2022
CeGaT Center for Human Genetics Tuebingen
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jan 27, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Porencephaly 2 Benign:2
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. -

Jan 01, 2019
Institute of Human Genetics, University of Leipzig Medical Center
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Optic nerve hypoplasia Pathogenic:1
-
Rare Disease Group, Clinical Genetics, Karolinska Institutet
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:research

- -

Inborn genetic diseases Benign:1
Jan 19, 2022
Ambry Genetics
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.62
BayesDel_addAF
Pathogenic
0.16
D
BayesDel_noAF
Pathogenic
0.41
CADD
Pathogenic
29
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.85
D
Eigen
Pathogenic
0.82
Eigen_PC
Pathogenic
0.72
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Pathogenic
0.99
D
M_CAP
Pathogenic
0.41
D
MetaRNN
Pathogenic
0.81
D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Uncertain
2.9
M
PhyloP100
9.5
PrimateAI
Uncertain
0.79
T
PROVEAN
Pathogenic
-5.8
D
REVEL
Pathogenic
0.90
Sift
Pathogenic
0.0
D
Sift4G
Pathogenic
0.0
D
Polyphen
1.0
D
Vest4
0.71
MVP
0.95
MPC
0.30
ClinPred
0.14
T
GERP RS
4.9
Varity_R
0.91
gMVP
0.80
Mutation Taster
=22/78
disease causing (ClinVar)

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: rs12877501; hg19: chr13-111164386; API