rs727502835

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PM1PP3

The NM_001849.4(COL6A2):​c.2508C>A​(p.Phe836Leu) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000149 in 1,610,162 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 34)
Exomes 𝑓: 0.000016 ( 0 hom. )

Consequence

COL6A2
NM_001849.4 missense

Scores

7
7
5

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 7.75

Publications

0 publications found
Variant links:
Genes affected
COL6A2 (HGNC:2212): (collagen type VI alpha 2 chain) This gene encodes one of the three alpha chains of type VI collagen, a beaded filament collagen found in most connective tissues. The product of this gene contains several domains similar to von Willebrand Factor type A domains. These domains have been shown to bind extracellular matrix proteins, an interaction that explains the importance of this collagen in organizing matrix components. Mutations in this gene are associated with Bethlem myopathy and Ullrich scleroatonic muscular dystrophy. Three transcript variants have been identified for this gene. [provided by RefSeq, Jul 2008]
COL6A2 Gene-Disease associations (from GenCC):
  • collagen 6-related myopathy
    Inheritance: AD, AR Classification: DEFINITIVE Submitted by: ClinGen
  • Ullrich congenital muscular dystrophy 1B
    Inheritance: AR, AD Classification: DEFINITIVE Submitted by: G2P
  • Bethlem myopathy 1A
    Inheritance: AD, AR Classification: STRONG Submitted by: Genomics England PanelApp
  • Ullrich congenital muscular dystrophy 1A
    Inheritance: AD, AR Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae), Genomics England PanelApp
  • Bethlem myopathy
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • Ullrich congenital muscular dystrophy
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • myosclerosis
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 3 ACMG points.

PM1
In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 6 benign, 7 uncertain in NM_001849.4
PP3
MetaRNN computational evidence supports a deleterious effect, 0.758

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
COL6A2NM_001849.4 linkc.2508C>A p.Phe836Leu missense_variant Exon 28 of 28 ENST00000300527.9 NP_001840.3 P12110-1A0A384MDP3

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
COL6A2ENST00000300527.9 linkc.2508C>A p.Phe836Leu missense_variant Exon 28 of 28 1 NM_001849.4 ENSP00000300527.4 P12110-1

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152224
Hom.:
0
Cov.:
34
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:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000166
AC:
4
AN:
240354
AF XY:
0.0000304
show subpopulations
Gnomad AFR exome
AF:
0.00
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:
0.0000372
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000158
AC:
23
AN:
1457938
Hom.:
0
Cov.:
33
AF XY:
0.0000152
AC XY:
11
AN XY:
725490
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33454
American (AMR)
AF:
0.00
AC:
0
AN:
44656
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26080
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39662
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86172
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
50456
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5762
European-Non Finnish (NFE)
AF:
0.0000198
AC:
22
AN:
1111442
Other (OTH)
AF:
0.00
AC:
0
AN:
60254
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.455
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:
0.00000657
AC:
1
AN:
152224
Hom.:
0
Cov.:
34
AF XY:
0.00
AC XY:
0
AN XY:
74362
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41458
American (AMR)
AF:
0.00
AC:
0
AN:
15292
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5190
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4832
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10622
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68042
Other (OTH)
AF:
0.00
AC:
0
AN:
2088
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.425
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:
0.0000384
Hom.:
0
Bravo
AF:
0.00000378
ExAC
AF:
0.00000829
AC:
1

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Bethlem myopathy 1A Uncertain:1
Feb 23, 2019
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces phenylalanine with leucine at codon 836 of the COL6A2 protein (p.Phe836Leu). The phenylalanine residue is highly conserved and there is a small physicochemical difference between phenylalanine and leucine. This variant is present in population databases (rs727502835, ExAC 0.002%) but has not been reported in the literature in individuals with a COL6A2-related disease. Algorithms developed to predict the effect of missense changes on protein structure and function do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). In summary, this variant is a rare missense change with uncertain impact on protein function. There is no indication that it causes disease, but the available evidence is currently insufficient to prove that conclusively. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.98
BayesDel_addAF
Pathogenic
0.23
D
BayesDel_noAF
Pathogenic
0.21
CADD
Pathogenic
26
DANN
Uncertain
1.0
DEOGEN2
Benign
0.24
T
Eigen
Uncertain
0.55
Eigen_PC
Uncertain
0.46
FATHMM_MKL
Uncertain
0.96
D
LIST_S2
Uncertain
0.92
D
M_CAP
Pathogenic
0.30
D
MetaRNN
Pathogenic
0.76
D
MetaSVM
Uncertain
0.42
D
MutationAssessor
Uncertain
2.6
M
PhyloP100
7.7
PrimateAI
Pathogenic
0.79
T
PROVEAN
Benign
-0.65
N
REVEL
Pathogenic
0.78
Sift
Benign
0.65
T
Sift4G
Benign
1.0
T
Polyphen
0.99
D
Vest4
0.49
MutPred
0.69
Loss of sheet (P = 0.0817);
MVP
0.82
MPC
0.66
ClinPred
0.86
D
GERP RS
4.2
Varity_R
0.21
gMVP
0.80
Mutation Taster
=14/86
disease causing

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: rs727502835; hg19: chr21-47551914; API