chr6-75086554-G-A

Position:

• chr6-75086554-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 3P and 2B. PM2 PP2 BP4_Moderate

The NM_004370.6(COL12A1):​c.9185C>T​(p.Ser3062Phe) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000206 in 1,453,068 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 (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: COL12A1 NM_004370.6 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 3.46

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]

ACMG classification

Verdict is Uncertain_significance. Variant got 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), COL12A1. . Gene score misZ 2.106 (greater than the threshold 3.09). Trascript score misZ 3.5535 (greater than threshold 3.09). GenCC has associacion of gene with Bethlem myopathy, Bethlem myopathy 2, Ullrich congenital muscular dystrophy 2, Ullrich congenital muscular dystrophy.
• BP4: Computational evidence support a benign effect (MetaRNN=0.12791586).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
COL12A1	NM_004370.6	c.9185C>T	p.Ser3062Phe	missense_variant	66/66	ENST00000322507.13	NP_004361.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
COL12A1	ENST00000322507.13	c.9185C>T	p.Ser3062Phe	missense_variant	66/66	1	NM_004370.6	ENSP00000325146.8

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000206 AC: 3 AN: 1453068 Hom.: 0 Cov.: 29 AF XY: 0.00000277 AC XY: 2 AN XY: 723126

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000350

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ExAC AF: 0.00000828 AC: 1

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

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

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Dec 11, 2021

This variant has not been reported in the literature in individuals affected with COL12A1-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces serine, which is neutral and polar, with phenylalanine, which is neutral and non-polar, at codon 3062 of the COL12A1 protein (p.Ser3062Phe). 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. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.093
BayesDel_addAF	Uncertain	0.071	D
BayesDel_noAF	Benign	-0.14
CADD	Uncertain	24
DANN	Uncertain	0.99
DEOGEN2	Benign	0.013	T;T;.;.
Eigen	Benign	-0.025
Eigen_PC	Uncertain	0.23
FATHMM_MKL	Uncertain	0.89	D
LIST_S2	Benign	0.76	T;T;T;T
M_CAP	Benign	0.011	T
MetaRNN	Benign	0.13	T;T;T;T
MetaSVM	Benign	-0.77	T
MutationAssessor	Benign	0.0	.;N;.;.
PrimateAI	Uncertain	0.57	T
PROVEAN	Benign	-0.28	.;N;N;N
REVEL	Uncertain	0.32
Sift	Pathogenic	0.0	.;D;D;D
Sift4G	Uncertain	0.028	D;D;D;D
Polyphen		0.0020, 0.0040	.;B;B;.
Vest4		0.090
MutPred		0.31		.;Loss of glycosylation at S3062 (P = 5e-04);.;.;
MVP		0.19
MPC		1.4
ClinPred		0.54	D
GERP RS		6.2
Varity_R		0.19
gMVP		0.34

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.11		Details are displayed if max score is > 0.2

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

Publications

LitVar

Other links and lift over

dbSNP: rs776138916; hg19: chr6-75796270;