6-75189255-C-T

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM2BP4_Moderate

The NM_004370.6(COL12A1):​c.785G>A​(p.Arg262Lys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000342 in 1,460,866 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 16/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R262G) has been classified as Uncertain significance.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 0.0000034 ( 0 hom. )

Consequence

COL12A1
NM_004370.6 missense

Scores

2
17

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 2.88

Publications

0 publications found
Variant links:
Genes affected
COL12A1 (HGNC:2188): (collagen type XII alpha 1 chain) This gene encodes the alpha chain of type XII collagen, a member of the FACIT (fibril-associated collagens with interrupted triple helices) collagen family. Type XII collagen is a homotrimer found in association with type I collagen, an association that is thought to modify the interactions between collagen I fibrils and the surrounding matrix. Alternatively spliced transcript variants encoding different isoforms have been identified. [provided by RefSeq, Jul 2008]
COL12A1 Gene-Disease associations (from GenCC):
  • Bethlem myopathy 2
    Inheritance: AD Classification: STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Orphanet
  • Bethlem myopathy 2
    Inheritance: AD Classification: STRONG, LIMITED Submitted by: Ambry Genetics, Illumina, Genomics England PanelApp
  • Ullrich congenital muscular dystrophy 2
    Inheritance: AR Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
  • 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.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.2263687).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
COL12A1NM_004370.6 linkc.785G>A p.Arg262Lys missense_variant Exon 7 of 66 ENST00000322507.13 NP_004361.3 Q99715-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
COL12A1ENST00000322507.13 linkc.785G>A p.Arg262Lys missense_variant Exon 7 of 66 1 NM_004370.6 ENSP00000325146.8 Q99715-1
COL12A1ENST00000345356.10 linkc.73+13465G>A intron_variant Intron 2 of 50 1 ENSP00000305147.9 Q99715-2
COL12A1ENST00000483888.6 linkc.785G>A p.Arg262Lys missense_variant Exon 7 of 65 5 ENSP00000421216.1 D6RGG3
COL12A1ENST00000416123.6 linkc.785G>A p.Arg262Lys missense_variant Exon 6 of 63 5 ENSP00000412864.2 Q99715-4

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD4 exome
AF:
0.00000342
AC:
5
AN:
1460866
Hom.:
0
Cov.:
31
AF XY:
0.00000688
AC XY:
5
AN XY:
726730
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33432
American (AMR)
AF:
0.000112
AC:
5
AN:
44626
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26088
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39664
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86200
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53318
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5762
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1111442
Other (OTH)
AF:
0.00
AC:
0
AN:
60334
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
1
2
2
3
4
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
GnomAD4 genome
Cov.:
32

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Uncertain:1
-
Breakthrough Genomics, Breakthrough Genomics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:not provided

- -

Bethlem myopathy 2;C4225314:Ullrich congenital muscular dystrophy 2 Uncertain:1
Feb 02, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces arginine, which is basic and polar, with lysine, which is basic and polar, at codon 262 of the COL12A1 protein (p.Arg262Lys). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with COL12A1-related conditions. ClinVar contains an entry for this variant (Variation ID: 475896). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is not expected to disrupt COL12A1 protein function with a negative predictive value of 80%. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.084
BayesDel_addAF
Benign
-0.021
T
BayesDel_noAF
Benign
-0.27
CADD
Benign
18
DANN
Benign
0.95
DEOGEN2
Benign
0.097
T;.;.
Eigen
Benign
-0.075
Eigen_PC
Benign
0.14
FATHMM_MKL
Uncertain
0.93
D
LIST_S2
Benign
0.81
T;T;T
M_CAP
Benign
0.030
D
MetaRNN
Benign
0.23
T;T;T
MetaSVM
Benign
-0.91
T
MutationAssessor
Benign
0.040
N;N;.
PhyloP100
2.9
PrimateAI
Uncertain
0.63
T
PROVEAN
Benign
-0.28
N;N;N
REVEL
Benign
0.25
Sift
Benign
0.41
T;T;T
Sift4G
Benign
0.68
T;T;T
Polyphen
0.12
B;.;.
Vest4
0.31
MutPred
0.43
Gain of ubiquitination at R262 (P = 0.0276);Gain of ubiquitination at R262 (P = 0.0276);Gain of ubiquitination at R262 (P = 0.0276);
MVP
0.51
MPC
0.57
ClinPred
0.58
D
GERP RS
5.7
Varity_R
0.22
gMVP
0.68
Mutation Taster
=87/13
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: rs1554188366; hg19: chr6-75898971; API