rs776981761

Variant names:

• chr6-75130893-G-A
• rs776981761
• NM_004370.6:c.6026C>T

Variant summary

Our verdict is Likely benign. The variant received -1 ACMG points: 0P and 1B. BP4

The NM_004370.6(COL12A1):​c.6026C>T​(p.Ser2009Leu) variant causes a missense change. The variant allele was found at a frequency of 0.00000434 in 1,613,938 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 (★★). Synonymous variant affecting the same amino acid position (i.e. S2009S) has been classified as Likely benign.

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0000041 (0 hom.)
• Consequence: COL12A1 NM_004370.6 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 4.58
• Publications: 0 publications found

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

ACMG classification

Our verdict: Likely_benign. The variant received -1 ACMG points.

• BP4: Computational evidence support a benign effect (MetaRNN=0.42260885).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_004370.6. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	COL12A1	NM_004370.6	MANE Select	c.6026C>T	p.Ser2009Leu	missense	Exon 36 of 66	NP_004361.3
	COL12A1	NM_001424113.1		c.6026C>T	p.Ser2009Leu	missense	Exon 36 of 66	NP_001411042.1
	COL12A1	NM_001424114.1		c.6005C>T	p.Ser2002Leu	missense	Exon 35 of 65	NP_001411043.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	COL12A1	ENST00000322507.13	TSL:1 MANE Select	c.6026C>T	p.Ser2009Leu	missense	Exon 36 of 66	ENSP00000325146.8
	COL12A1	ENST00000345356.10	TSL:1	c.2534C>T	p.Ser845Leu	missense	Exon 21 of 51	ENSP00000305147.9
	COL12A1	ENST00000483888.6	TSL:5	c.6026C>T	p.Ser2009Leu	missense	Exon 36 of 65	ENSP00000421216.1

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152110 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

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: 0.0000160 AC: 4 AN: 249380 AF XY: 0.0000222

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: 0.0000354

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000410 AC: 6 AN: 1461828 Hom.: 0 Cov.: 31 AF XY: 0.00000550 AC XY: 4 AN XY: 727214

African (AFR) AF: 0.00 AC: 0 AN: 33476

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39696

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53414

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00000540 AC: 6 AN: 1111970

Other (OTH) AF: 0.00 AC: 0 AN: 60386

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152110 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74296

African (AFR) AF: 0.00 AC: 0 AN: 41410

American (AMR) AF: 0.00 AC: 0 AN: 15270

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3470

East Asian (EAS) AF: 0.00 AC: 0 AN: 5182

South Asian (SAS) AF: 0.00 AC: 0 AN: 4824

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10612

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.0000147 AC: 1 AN: 68024

Other (OTH) AF: 0.00 AC: 0 AN: 2090

Alfa AF: 0.0000659 Hom.: 0

ExAC AF: 0.0000248 AC: 3

EpiCase AF: 0.00

EpiControl AF: 0.000119

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Inborn genetic diseases Uncertain:1

Feb 06, 2024

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.6026C>T (p.S2009L) alteration is located in exon 36 (coding exon 35) of the COL12A1 gene. This alteration results from a C to T substitution at nucleotide position 6026, causing the serine (S) at amino acid position 2009 to be replaced by a leucine (L). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear.

Bethlem myopathy 2;C4225314:Ullrich congenital muscular dystrophy 2 Uncertain:1

Dec 30, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces serine, which is neutral and polar, with leucine, which is neutral and non-polar, at codon 2009 of the COL12A1 protein (p.Ser2009Leu). This variant is present in population databases (rs776981761, gnomAD 0.004%). 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: 475882). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae 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 v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.11
BayesDel_addAF	Benign	-0.13	T
BayesDel_noAF	Benign	-0.32
CADD	Uncertain	24
DANN	Uncertain	1.0
DEOGEN2	Benign	0.027	T
Eigen	Uncertain	0.29
Eigen_PC	Uncertain	0.33
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Pathogenic	0.98	D
M_CAP	Benign	0.030	D
MetaRNN	Benign	0.42	T
MetaSVM	Benign	-0.90	T
MutationAssessor	Uncertain	2.0	M
PhyloP100		4.6
PrimateAI	Uncertain	0.58	T
PROVEAN	Benign	-1.5	N
REVEL	Benign	0.23
Sift	Benign	0.067	T
Sift4G	Pathogenic	0.0010	D
Polyphen		0.52	P
Vest4		0.55
MutPred		0.63		Loss of disorder (P = 0.0321)
MVP		0.36
MPC		0.14
ClinPred		0.33	T
GERP RS		5.6
Varity_R		0.081
gMVP		0.39
Mutation Taster		=65/35	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs776981761; hg19: chr6-75840609; COSMIC: COSV59392153; COSMIC: COSV59392153;