rs200720222

Variant summary

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

The NM_004369.4(COL6A3):​c.1006C>T​(p.Arg336Trp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000335 in 1,613,944 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R336Q) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000035 ( 0 hom. )

Consequence

COL6A3
NM_004369.4 missense

Scores

11
8

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:4B:1

Conservation

PhyloP100: 0.568

Publications

3 publications found
Variant links:
Genes affected
COL6A3 (HGNC:2213): (collagen type VI alpha 3 chain) This gene encodes the alpha-3 chain, one of the three alpha chains of type VI collagen, a beaded filament collagen found in most connective tissues. The alpha-3 chain of type VI collagen is much larger than the alpha-1 and -2 chains. This difference in size is largely due to an increase in the number of subdomains, similar to von Willebrand Factor type A domains, that are found in the amino terminal globular domain of all the alpha chains. 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 the type VI collagen genes are associated with Bethlem myopathy, a rare autosomal dominant proximal myopathy with early childhood onset. Mutations in this gene are also a cause of Ullrich congenital muscular dystrophy, also referred to as Ullrich scleroatonic muscular dystrophy, an autosomal recessive congenital myopathy that is more severe than Bethlem myopathy. Multiple transcript variants have been identified, but the full-length nature of only some of these variants has been described. [provided by RefSeq, Jun 2009]
COL6A3 Gene-Disease associations (from GenCC):
  • Bethlem myopathy 1A
    Inheritance: AD, AR, SD Classification: DEFINITIVE, STRONG Submitted by: Genomics England PanelApp, Ambry Genetics
  • collagen 6-related myopathy
    Inheritance: AD, AR Classification: DEFINITIVE Submitted by: ClinGen
  • Ullrich congenital muscular dystrophy 1C
    Inheritance: AR Classification: DEFINITIVE Submitted by: G2P
  • dystonia 27
    Inheritance: AR Classification: STRONG, SUPPORTIVE, LIMITED, NO_KNOWN Submitted by: Illumina, Labcorp Genetics (formerly Invitae), ClinGen, Ambry Genetics, Orphanet
  • Ullrich congenital muscular dystrophy 1A
    Inheritance: AR, AD, SD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics, Genomics England PanelApp
  • Bethlem myopathy
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • Ullrich congenital muscular dystrophy
    Inheritance: AD 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 0 ACMG points.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
COL6A3NM_004369.4 linkc.1006C>T p.Arg336Trp missense_variant Exon 4 of 44 ENST00000295550.9 NP_004360.2 P12111-1D9ZGF2Q8N4Z1Q63HQ4

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
COL6A3ENST00000295550.9 linkc.1006C>T p.Arg336Trp missense_variant Exon 4 of 44 1 NM_004369.4 ENSP00000295550.4 P12111-1

Frequencies

GnomAD3 genomes
AF:
0.0000197
AC:
3
AN:
152212
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000131
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:
0.0000478
AC:
12
AN:
250794
AF XY:
0.0000221
show subpopulations
Gnomad AFR exome
AF:
0.0000620
Gnomad AMR exome
AF:
0.000203
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000265
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000349
AC:
51
AN:
1461732
Hom.:
0
Cov.:
32
AF XY:
0.0000289
AC XY:
21
AN XY:
727148
show subpopulations
African (AFR)
AF:
0.0000896
AC:
3
AN:
33470
American (AMR)
AF:
0.000224
AC:
10
AN:
44716
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26128
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39692
South Asian (SAS)
AF:
0.0000232
AC:
2
AN:
86240
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53398
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000315
AC:
35
AN:
1111940
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60380
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.469
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

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:
0.0000197
AC:
3
AN:
152212
Hom.:
0
Cov.:
33
AF XY:
0.0000269
AC XY:
2
AN XY:
74354
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41460
American (AMR)
AF:
0.000131
AC:
2
AN:
15284
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5186
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4822
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10626
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68040
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
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

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:
0.000381
Hom.:
0
Bravo
AF:
0.0000378
ESP6500AA
AF:
0.000227
AC:
1
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.0000412
AC:
5
EpiCase
AF:
0.0000545
EpiControl
AF:
0.000119

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:4Benign:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:3
Jan 03, 2023
Revvity Omics, Revvity
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Oct 25, 2016
Eurofins Ntd Llc (ga)
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jul 16, 2021
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Reported in heterozygous state as a variant of uncertain significance in an individual with clinically suspected limb-girdle muscular dystrophy (Nallamilli et al., 2018); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 30564623, 27535533) -

not specified Uncertain:1
Mar 17, 2025
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: COL6A3 c.1006C>T (p.Arg336Trp) results in a non-conservative amino acid change in the encoded protein sequence. Three of four in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 4.8e-05 in 250794 control chromosomes (gnomAD). This frequency is not significantly higher than estimated for a pathogenic variant in COL6A3 causing Ullrich congenital muscular dystrophy 1-AR (4.8e-05 vs 0.0035), allowing no conclusion about variant significance. c.1006C>T has been reported in the literature in the heterozygous state in an individual with suspected limb-girdle muscular dystrophy (Nallamilli_2018). This report does not provide unequivocal conclusions about association of the variant with Ullrich congenital muscular dystrophy 1-AR. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. The following publication has been ascertained in the context of this evaluation (PMID: 30564623). ClinVar contains an entry for this variant (Variation ID: 497851). Based on the evidence outlined above, the variant was classified as uncertain significance. -

Bethlem myopathy 1A Benign:1
Nov 27, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.10
BayesDel_addAF
Benign
-0.13
T
BayesDel_noAF
Benign
-0.16
CADD
Benign
22
DANN
Uncertain
1.0
DEOGEN2
Benign
0.29
.;T;.;.;T;T
Eigen
Uncertain
0.31
Eigen_PC
Uncertain
0.29
FATHMM_MKL
Uncertain
0.85
D
LIST_S2
Uncertain
0.92
D;D;.;D;D;D
M_CAP
Uncertain
0.18
D
MetaRNN
Uncertain
0.45
T;T;T;T;T;T
MetaSVM
Uncertain
-0.22
T
MutationAssessor
Benign
1.6
.;L;.;.;.;.
PhyloP100
0.57
PrimateAI
Benign
0.36
T
PROVEAN
Benign
-1.9
N;N;N;D;D;.
REVEL
Uncertain
0.56
Sift
Uncertain
0.014
D;D;D;D;D;.
Sift4G
Uncertain
0.0020
D;D;D;D;D;D
Polyphen
1.0
D;D;D;.;.;.
Vest4
0.53
MVP
0.95
MPC
0.65
ClinPred
0.34
T
GERP RS
4.9
Varity_R
0.14
gMVP
0.40
Mutation Taster
=76/24
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: rs200720222; hg19: chr2-238296531; API