1-36097805-C-A

Variant summary

Our verdict is Likely benign. The variant received -5 ACMG points: 0P and 5B. BP4BS2

The NM_005202.4(COL8A2):​c.1876G>T​(p.Val626Leu) variant causes a missense change. The variant allele was found at a frequency of 0.0000186 in 1,613,632 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (no stars).

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000019 ( 0 hom. )

Consequence

COL8A2
NM_005202.4 missense

Scores

2
8
9

Clinical Significance

Uncertain significance no assertion criteria provided U:1

Conservation

PhyloP100: 3.78

Publications

0 publications found
Variant links:
Genes affected
COL8A2 (HGNC:2216): (collagen type VIII alpha 2 chain) This gene encodes the alpha 2 chain of type VIII collagen. This protein is a major component of the basement membrane of the corneal endothelium and forms homo- or heterotrimers with alpha 1 (VIII) type collagens. Defects in this gene are associated with Fuchs endothelial corneal dystrophy and posterior polymorphous corneal dystrophy type 2. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jun 2014]
COL8A2 Gene-Disease associations (from GenCC):
  • corneal dystrophy, Fuchs endothelial, 1
    Inheritance: AD Classification: STRONG Submitted by: G2P
  • posterior polymorphous corneal dystrophy 2
    Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
  • Fuchs' endothelial dystrophy
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • posterior polymorphous corneal dystrophy
    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 -5 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.3961565).
BS2
High AC in GnomAdExome4 at 28 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
COL8A2NM_005202.4 linkc.1876G>T p.Val626Leu missense_variant Exon 4 of 4 ENST00000397799.2 NP_005193.1 P25067
COL8A2NM_001294347.2 linkc.1681G>T p.Val561Leu missense_variant Exon 4 of 4 NP_001281276.1 P25067E9PP49

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
COL8A2ENST00000397799.2 linkc.1876G>T p.Val626Leu missense_variant Exon 4 of 4 5 NM_005202.4 ENSP00000380901.1 P25067
COL8A2ENST00000481785.1 linkc.1681G>T p.Val561Leu missense_variant Exon 2 of 2 1 ENSP00000436433.1 E9PP49
COL8A2ENST00000303143.9 linkc.1876G>T p.Val626Leu missense_variant Exon 2 of 2 2 ENSP00000305913.4 P25067

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152228
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000241
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:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000119
AC:
3
AN:
251258
AF XY:
0.00000736
show subpopulations
Gnomad AFR exome
AF:
0.0000616
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000880
Gnomad OTH exome
AF:
0.000163
GnomAD4 exome
AF:
0.0000192
AC:
28
AN:
1461404
Hom.:
0
Cov.:
37
AF XY:
0.0000151
AC XY:
11
AN XY:
727036
show subpopulations
African (AFR)
AF:
0.0000299
AC:
1
AN:
33480
American (AMR)
AF:
0.0000224
AC:
1
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:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
52942
Middle Eastern (MID)
AF:
0.000347
AC:
2
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000198
AC:
22
AN:
1112002
Other (OTH)
AF:
0.0000331
AC:
2
AN:
60394
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.500
Heterozygous variant carriers
0
3
5
8
10
13
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
AF:
0.0000131
AC:
2
AN:
152228
Hom.:
0
Cov.:
33
AF XY:
0.0000134
AC XY:
1
AN XY:
74368
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41464
American (AMR)
AF:
0.00
AC:
0
AN:
15286
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5200
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10624
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68034
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.450
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.0000658
Hom.:
0
Bravo
AF:
0.00000756

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: no assertion criteria provided
LINK: link

Submissions by phenotype

not provided Uncertain:1
-
Department of Pathology and Laboratory Medicine, Sinai Health System
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

The COL8A2 p.Val561Leu variant was not identified in the literature nor was it identified in ClinVar or LOVD 3.0. The variant was identified in dbSNP (ID: rs928614322) and in control databases in 3 of 251258 chromosomes at a frequency of 0.00001194 (Genome Aggregation Database March 6, 2019, v2.1.1). The variant was observed in the following populations: Other in 1 of 6132 chromosomes (freq: 0.000163), African in 1 of 16240 chromosomes (freq: 0.000062) and European (non-Finnish) in 1 of 113630 chromosomes (freq: 0.000009), but was not observed in the Latino, Ashkenazi Jewish, East Asian, European (Finnish), or South Asian populations. The p.Val561 residue is conserved in mammals and computational analyses (PolyPhen-2, SIFT, AlignGVGD, BLOSUM, MutationTaster) do not suggest a high likelihood of impact to the protein; this information is not very predictive of pathogenicity. The variant occurs outside of the splicing consensus sequence and 1 of 4 in silico or computational prediction software programs (SpliceSiteFinder, MaxEntScan, NNSPLICE, GeneSplicer) predict a greater than 10% difference in splicing; this is not very predictive of pathogenicity. In summary, based on the above information the clinical significance of this variant cannot be determined with certainty at this time. This variant is classified as a variant of uncertain significance. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.59
BayesDel_addAF
Benign
-0.098
T
BayesDel_noAF
Benign
-0.20
CADD
Uncertain
24
DANN
Uncertain
1.0
DEOGEN2
Benign
0.25
T;T;.
Eigen
Uncertain
0.32
Eigen_PC
Uncertain
0.38
FATHMM_MKL
Uncertain
0.81
D
LIST_S2
Benign
0.85
.;T;T
M_CAP
Benign
0.043
D
MetaRNN
Benign
0.40
T;T;T
MetaSVM
Uncertain
0.049
D
MutationAssessor
Benign
1.5
L;L;.
PhyloP100
3.8
PrimateAI
Pathogenic
0.79
T
PROVEAN
Benign
-0.96
N;N;N
REVEL
Uncertain
0.42
Sift
Uncertain
0.010
D;D;D
Sift4G
Uncertain
0.021
D;D;T
Polyphen
0.24
B;B;.
Vest4
0.40
MutPred
0.66
Loss of sheet (P = 0.0817);Loss of sheet (P = 0.0817);.;
MVP
0.62
MPC
0.97
ClinPred
0.72
D
GERP RS
4.6
Varity_R
0.41
gMVP
0.38
Mutation Taster
=58/42
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.020
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: rs928614322; hg19: chr1-36563406; API