rs886049441

Variant names:

• chr12-47973001-T-C
• rs886049441
• NM_001844.5:c.*406A>G

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_001844.5(COL2A1):​c.*406A>G variant causes a 3 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000399 in 501,128 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: 𝑓 0.0000066 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0000029 (0 hom.)
• Consequence: COL2A1 NM_001844.5 3_prime_UTR
• Clinical Significance: Uncertain significance criteria provided, single submitter U:2
• Conservation: PhyloP100: 2.33
• Publications: 0 publications found

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)

ACMG classification

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 (BayesDel_noAF=-0.36).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
COL2A1	NM_001844.5	c.*406A>G		3_prime_UTR_variant	Exon 54 of 54	ENST00000380518.8	NP_001835.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
COL2A1	ENST00000380518.8	c.*406A>G		3_prime_UTR_variant	Exon 54 of 54	1	NM_001844.5	ENSP00000369889.3
COL2A1	ENST00000493991.5	n.*200A>G		downstream_gene_variant		2

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152158 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: 0.000207

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.00000287 AC: 1 AN: 348970 Hom.: 0 Cov.: 0 AF XY: 0.00000560 AC XY: 1 AN XY: 178680

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 11444

American (AMR) AF: 0.00 AC: 0 AN: 13136

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 11734

East Asian (EAS) AF: 0.0000343 AC: 1 AN: 29174

South Asian (SAS) AF: 0.00 AC: 0 AN: 17206

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 24532

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 1670

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 218466

Other (OTH) AF: 0.00 AC: 0 AN: 21608

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.000000), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152158 Hom.: 0 Cov.: 32 AF XY: 0.0000135 AC XY: 1 AN XY: 74322

African (AFR) AF: 0.00 AC: 0 AN: 41444

American (AMR) AF: 0.00 AC: 0 AN: 15278

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3472

East Asian (EAS) AF: 0.00 AC: 0 AN: 5194

South Asian (SAS) AF: 0.000207 AC: 1 AN: 4824

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10600

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

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 68024

Other (OTH) AF: 0.00 AC: 0 AN: 2094

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, single submitter

Submissions by phenotype

Stickler syndrome type 1 Uncertain:1

Jan 12, 2018

Illumina Laboratory Services, Illumina

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Type II Collagenopathies Uncertain:1

Jan 12, 2018

Illumina Laboratory Services, Illumina

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.36
CADD	Benign	16
DANN	Benign	0.87
PhyloP100		2.3

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

Other links and lift over

dbSNP: rs886049441; hg19: chr12-48366784;