12-47984115-G-T

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2PP2

The NM_001844.5(COL2A1):​c.1913C>A​(p.Thr638Lys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,386 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. T638I) has been classified as Benign.

Frequency

Genomes: not found (cov: 33)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

COL2A1
NM_001844.5 missense

Scores

1
10
8

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 2.00
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 3 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP2
Missense variant in the COL2A1 gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 376 curated pathogenic missense variants (we use a threshold of 10). The gene has 125 curated benign missense variants. Gene score misZ: 3.2926 (above the threshold of 3.09). Trascript score misZ: 5.3726 (above the threshold of 3.09). GenCC associations: The gene is linked to spondylometaphyseal dysplasia, Schmidt type, spondyloepiphyseal dysplasia congenita, hypochondrogenesis, autosomal dominant rhegmatogenous retinal detachment, spondyloperipheral dysplasia, Kniest dysplasia, familial avascular necrosis of femoral head, spondylometaphyseal dysplasia, mild spondyloepiphyseal dysplasia due to COL2A1 mutation with early-onset osteoarthritis, otospondylomegaepiphyseal dysplasia, autosomal recessive, multiple epiphyseal dysplasia, Beighton type, otospondylomegaepiphyseal dysplasia, Legg-Calve-Perthes disease, achondrogenesis type II, spondyloepiphyseal dysplasia, Stanescu type, platyspondylic dysplasia, Torrance type, Stickler syndrome type 1, dysspondyloenchondromatosis, vitreoretinopathy with phalangeal epiphyseal dysplasia, Stickler syndrome, type I, nonsyndromic ocular, avascular necrosis of femoral head, primary, 1, spondyloepiphyseal dysplasia with metatarsal shortening, spondyloepimetaphyseal dysplasia, Strudwick type.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
COL2A1NM_001844.5 linkc.1913C>A p.Thr638Lys missense_variant Exon 29 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.1913C>A p.Thr638Lys missense_variant Exon 29 of 54 1 NM_001844.5 ENSP00000369889.3 P02458-2
COL2A1ENST00000337299.7 linkc.1706C>A p.Thr569Lys missense_variant Exon 28 of 53 1 ENSP00000338213.6 P02458-1
COL2A1ENST00000493991.5 linkn.837C>A non_coding_transcript_exon_variant Exon 12 of 37 2

Frequencies

GnomAD3 genomes
Cov.:
33
GnomAD3 exomes
AF:
0.00000401
AC:
1
AN:
249176
Hom.:
0
AF XY:
0.00
AC XY:
0
AN XY:
135076
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 SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000888
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
6.84e-7
AC:
1
AN:
1461386
Hom.:
0
Cov.:
33
AF XY:
0.00
AC XY:
0
AN XY:
726944
show subpopulations
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:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
8.99e-7
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
Cov.:
33

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

not provided Uncertain:1
Apr 18, 2021
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This variant has not been reported in the literature in individuals with COL2A1-related conditions. 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. 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 COL2A1 protein function. This variant is not present in population databases (ExAC no frequency). This sequence change replaces threonine with lysine at codon 638 of the COL2A1 protein (p.Thr638Lys). The threonine residue is highly conserved and there is a moderate physicochemical difference between threonine and lysine. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.46
BayesDel_addAF
Pathogenic
0.23
D
BayesDel_noAF
Uncertain
0.10
CADD
Benign
23
DANN
Uncertain
0.99
DEOGEN2
Benign
0.37
T;.
Eigen
Benign
0.13
Eigen_PC
Uncertain
0.28
FATHMM_MKL
Uncertain
0.96
D
LIST_S2
Uncertain
0.87
D;D
M_CAP
Benign
0.063
D
MetaRNN
Uncertain
0.50
T;T
MetaSVM
Uncertain
0.34
D
MutationAssessor
Benign
0.050
N;.
PrimateAI
Uncertain
0.73
T
PROVEAN
Benign
-1.0
N;N
REVEL
Uncertain
0.52
Sift
Benign
0.95
T;T
Sift4G
Benign
0.21
T;T
Polyphen
0.76
P;P
Vest4
0.52
MutPred
0.29
Loss of phosphorylation at T638 (P = 0.0046);.;
MVP
0.87
MPC
1.3
ClinPred
0.62
D
GERP RS
5.2
Varity_R
0.32
gMVP
0.55

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

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs41263847; hg19: chr12-48377898; COSMIC: COSV61528076; COSMIC: COSV61528076; API