12-47981803-AG-AGG

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong

The NM_001844.5(COL2A1):​c.2381dupC​(p.Gly795TrpfsTer6) variant causes a frameshift change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000713 in 1,402,272 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★★). Synonymous variant affecting the same amino acid position (i.e. P794P) has been classified as Likely benign. Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: not found (cov: 33)
Exomes 𝑓: 7.1e-7 ( 0 hom. )

Consequence

COL2A1
NM_001844.5 frameshift

Scores

Not classified

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:2

Conservation

PhyloP100: 9.89

Publications

0 publications found
Variant links:
Genes affected
COL2A1 (HGNC:2200): (collagen type II alpha 1 chain) This gene encodes the alpha-1 chain of type II collagen, a fibrillar collagen found in cartilage and the vitreous humor of the eye. Mutations in this gene are associated with achondrogenesis, chondrodysplasia, early onset familial osteoarthritis, SED congenita, Langer-Saldino achondrogenesis, Kniest dysplasia, Stickler syndrome type I, and spondyloepimetaphyseal dysplasia Strudwick type. In addition, defects in processing chondrocalcin, a calcium binding protein that is the C-propeptide of this collagen molecule, are also associated with chondrodysplasia. There are two transcripts identified for this gene. [provided by RefSeq, Jul 2008]
COL2A1 Gene-Disease associations (from GenCC):
  • achondrogenesis type II
    Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Ambry Genetics, ClinGen, G2P, Orphanet, Labcorp Genetics (formerly Invitae)
  • Kniest dysplasia
    Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: G2P, Orphanet, ClinGen, Labcorp Genetics (formerly Invitae)
  • platyspondylic dysplasia, Torrance type
    Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: ClinGen, Orphanet
  • spondyloepimetaphyseal dysplasia, Strudwick type
    Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: G2P, Orphanet
  • spondyloepiphyseal dysplasia congenita
    Inheritance: AD, AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: ClinGen, G2P, Orphanet, Labcorp Genetics (formerly Invitae)
  • spondyloepiphyseal dysplasia with metatarsal shortening
    Inheritance: AD Classification: DEFINITIVE, STRONG, MODERATE, SUPPORTIVE Submitted by: ClinGen, Orphanet, Ambry Genetics, Labcorp Genetics (formerly Invitae)
  • spondylometaphyseal dysplasia
    Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
  • spondyloperipheral dysplasia
    Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: ClinGen, Orphanet
  • Stickler syndrome type 1
    Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: PanelApp Australia, ClinGen, Illumina, Orphanet, Genomics England PanelApp
  • Stickler syndrome, type I, nonsyndromic ocular
    Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae)
  • avascular necrosis of femoral head, primary, 1
    Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
  • Legg-Calve-Perthes disease
    Inheritance: AD Classification: STRONG, SUPPORTIVE Submitted by: Orphanet, Labcorp Genetics (formerly Invitae)
  • mild spondyloepiphyseal dysplasia due to COL2A1 mutation with early-onset osteoarthritis
    Inheritance: AD Classification: STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Orphanet
  • otospondylomegaepiphyseal dysplasia, autosomal recessive
    Inheritance: AD, AR Classification: STRONG, LIMITED Submitted by: Labcorp Genetics (formerly Invitae)
  • spondyloepiphyseal dysplasia, Stanescu type
    Inheritance: AD Classification: MODERATE, SUPPORTIVE Submitted by: ClinGen, Orphanet
  • autosomal dominant rhegmatogenous retinal detachment
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • dysspondyloenchondromatosis
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • familial avascular necrosis of femoral head
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • hypochondrogenesis
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • multiple epiphyseal dysplasia, Beighton type
    Inheritance: AD Classification: SUPPORTIVE, LIMITED Submitted by: Orphanet, Labcorp Genetics (formerly Invitae)
  • spondylometaphyseal dysplasia, Schmidt type
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • otospondylomegaepiphyseal dysplasia
    Inheritance: AR Classification: LIMITED Submitted by: Ambry Genetics
  • vitreoretinopathy with phalangeal epiphyseal dysplasia
    Inheritance: Unknown Classification: LIMITED Submitted by: Labcorp Genetics (formerly Invitae)

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 18 ACMG points.

PVS1
Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 12-47981803-A-AG is Pathogenic according to our data. Variant chr12-47981803-A-AG is described in ClinVar as Pathogenic. ClinVar VariationId is 1076267.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
COL2A1NM_001844.5 linkc.2381dupC p.Gly795TrpfsTer6 frameshift_variant Exon 36 of 54 ENST00000380518.8 NP_001835.3 P02458-2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
COL2A1ENST00000380518.8 linkc.2381dupC p.Gly795TrpfsTer6 frameshift_variant Exon 36 of 54 1 NM_001844.5 ENSP00000369889.3 P02458-2
COL2A1ENST00000337299.7 linkc.2174dupC p.Gly726TrpfsTer6 frameshift_variant Exon 35 of 53 1 ENSP00000338213.6 P02458-1
COL2A1ENST00000483376.1 linkn.559dupC non_coding_transcript_exon_variant Exon 7 of 8 5
COL2A1ENST00000493991.5 linkn.1467dupC non_coding_transcript_exon_variant Exon 19 of 37 2

Frequencies

GnomAD3 genomes
Cov.:
33
GnomAD2 exomes
AF:
0.00000621
AC:
1
AN:
160966
AF XY:
0.00
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:
0.0000158
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
7.13e-7
AC:
1
AN:
1402272
Hom.:
0
Cov.:
36
AF XY:
0.00
AC XY:
0
AN XY:
692044
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
31692
American (AMR)
AF:
0.00
AC:
0
AN:
36072
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25210
East Asian (EAS)
AF:
0.00
AC:
0
AN:
35884
South Asian (SAS)
AF:
0.00
AC:
0
AN:
79510
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
49416
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5662
European-Non Finnish (NFE)
AF:
9.25e-7
AC:
1
AN:
1080660
Other (OTH)
AF:
0.00
AC:
0
AN:
58166
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.575
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
GnomAD4 genome
Cov.:
33

ClinVar

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

Submissions by phenotype

not provided Pathogenic:2
May 23, 2024
GeneDx
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Frameshift variant predicted to result in protein truncation or nonsense mediated decay in a gene for which loss of function is a known mechanism of disease; Not observed at significant frequency in large population cohorts (gnomAD); This variant is associated with the following publications: (PMID: 16752401, 20179744) -

Jul 23, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change creates a premature translational stop signal (p.Gly795Trpfs*6) in the COL2A1 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in COL2A1 are known to be pathogenic (PMID: 20179744). The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. This premature translational stop signal has been observed in individuals with Stickler syndrome (PMID: 16752401, 20179744). ClinVar contains an entry for this variant (Variation ID: 1076267). For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
PhyloP100
9.9
Mutation Taster
=0/200
disease causing (fs/PTC)

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: rs1555166218; hg19: chr12-48375586; API