chr12-47974090-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 5P and 4B. PM1PP2PP3_ModerateBS2

The NM_001844.5(COL2A1):​c.4316C>T​(p.Thr1439Met) variant causes a missense, splice region change. The variant allele was found at a frequency of 0.000044 in 1,614,060 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 2/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.000053 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000043 ( 0 hom. )

Consequence

COL2A1
NM_001844.5 missense, splice_region

Scores

3
11
5
Splicing: ADA: 0.9916
2

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:2U:3

Conservation

PhyloP100: 4.34
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 1 ACMG points.

PM1
In a domain Fibrillar collagen NC1 (size 234) in uniprot entity CO2A1_HUMAN there are 26 pathogenic changes around while only 1 benign (96%) in NM_001844.5
PP2
Missense variant in gene, where missense usually causes diseases (based on misZ statistic), COL2A1. . Gene score misZ 3.2926 (greater than the threshold 3.09). Trascript score misZ 5.3726 (greater than threshold 3.09). GenCC has associacion of gene with 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.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.891
BS2
High AC in GnomAd4 at 8 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
COL2A1NM_001844.5 linkuse as main transcriptc.4316C>T p.Thr1439Met missense_variant, splice_region_variant 53/54 ENST00000380518.8 NP_001835.3 P02458-2

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
COL2A1ENST00000380518.8 linkuse as main transcriptc.4316C>T p.Thr1439Met missense_variant, splice_region_variant 53/541 NM_001844.5 ENSP00000369889.3 P02458-2
COL2A1ENST00000337299.7 linkuse as main transcriptc.4109C>T p.Thr1370Met missense_variant, splice_region_variant 52/531 ENSP00000338213.6 P02458-1
COL2A1ENST00000493991.5 linkuse as main transcriptn.3402C>T splice_region_variant, non_coding_transcript_exon_variant 36/372

Frequencies

GnomAD3 genomes
AF:
0.0000526
AC:
8
AN:
152184
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000241
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000654
Gnomad ASJ
AF:
0.000577
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000588
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000797
AC:
20
AN:
251026
Hom.:
0
AF XY:
0.0000958
AC XY:
13
AN XY:
135678
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.000173
Gnomad ASJ exome
AF:
0.000496
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.0000653
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000441
Gnomad OTH exome
AF:
0.000326
GnomAD4 exome
AF:
0.0000431
AC:
63
AN:
1461876
Hom.:
0
Cov.:
34
AF XY:
0.0000440
AC XY:
32
AN XY:
727236
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.000112
Gnomad4 ASJ exome
AF:
0.000574
Gnomad4 EAS exome
AF:
0.0000252
Gnomad4 SAS exome
AF:
0.0000696
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000261
Gnomad4 OTH exome
AF:
0.000116
GnomAD4 genome
AF:
0.0000526
AC:
8
AN:
152184
Hom.:
0
Cov.:
32
AF XY:
0.0000538
AC XY:
4
AN XY:
74332
show subpopulations
Gnomad4 AFR
AF:
0.0000241
Gnomad4 AMR
AF:
0.0000654
Gnomad4 ASJ
AF:
0.000577
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000588
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000790
Hom.:
0
Bravo
AF:
0.0000907
ExAC
AF:
0.0000576
AC:
7
EpiCase
AF:
0.000109
EpiControl
AF:
0.000119

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:2Uncertain:3
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Spondyloepiphyseal dysplasia congenita Pathogenic:1Uncertain:1
Pathogenic, no assertion criteria providedliterature onlyOMIMNov 22, 2001- -
Uncertain significance, criteria provided, single submitterclinical testingGenomic Research Center, Shahid Beheshti University of Medical SciencesJan 01, 2019- -
Spondyloperipheral dysplasia Pathogenic:1
Likely pathogenic, criteria provided, single submitterclinical testingLaboratory for Molecular Medicine, Mass General Brigham Personalized MedicineSep 15, 2014The Thr1439Met variant in COL2A1 has been reported as de novo in one individual with spondyloepiphyseal dysplasia congenita and was shown to segregate with disease in 2 affected sons* (Unger 2001). This variant was not identified in large population studies. Computational analyses (biochemical amino acid properties, conservation, PolyPhen2, and SIFT) suggest that the Thr1439Met variant may impact the protein, though this information is not predictive enough to determine pathogenicity. In addition, this variant is located near the 5' splice region. Computational tools do not suggest an impact to splicing, though this information is not predictive enough to rule out pathogenicity. In summary, although additional studies are required to fully establish its clinical significance, the Thr1439Met variant is likely pathogenic for spondyloepiphyseal dysplasia congenita in an autosomal dominant manner. -
COL2A1-related disorder Uncertain:1
Uncertain significance, no assertion criteria providedclinical testingPreventionGenetics, part of Exact SciencesMar 15, 2024The COL2A1 c.4316C>T variant is predicted to result in the amino acid substitution p.Thr1439Met. This variant, also described as p.Thr1370Met, was reported to be de novo in an in an individual with spondyloepiphyseal dysplasia congenita; however, parentage is not known to have been confirmed (Unger et al. 2001. PubMed ID: 11746045). In this family, the variant segregate with disease among two offspring of the proband, one of which was affected by a second skeletal dysplasia. This variant was also found in an individual with Kneist dysplasia (Table 1, Barat-Houari et al. 2015. PubMed ID: 26626311) and in an individual with atypical Stickler syndrome and retinitis pigmentosa (Breazzano et al. 2020. PubMed ID: 32381255). This variant is reported in 0.058% of alleles in individuals of Ashkenazi Jewish descent in gnomAD, which is more common than expected for a primary cause of disease. At this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. -
not provided Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpJan 18, 2024This sequence change replaces threonine, which is neutral and polar, with methionine, which is neutral and non-polar, at codon 1439 of the COL2A1 protein (p.Thr1439Met). This variant is present in population databases (rs121912886, gnomAD 0.06%). This missense change has been observed in individual(s) with retinitis pigmentosa and/or spondyloepiphyseal dysplasia congenita (PMID: 11746045, 32381255). It has also been observed to segregate with disease in related individuals. This variant is also known as T1370M. ClinVar contains an entry for this variant (Variation ID: 17385). Experimental studies and prediction algorithms are not available or were not evaluated, and the functional significance of this variant is currently unknown. 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 v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.14
BayesDel_addAF
Benign
0.0049
T
BayesDel_noAF
Uncertain
0.040
CADD
Pathogenic
31
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.79
D;.
Eigen
Uncertain
0.59
Eigen_PC
Uncertain
0.58
FATHMM_MKL
Uncertain
0.92
D
LIST_S2
Pathogenic
0.98
D;D
M_CAP
Benign
0.066
D
MetaRNN
Pathogenic
0.89
D;D
MetaSVM
Uncertain
-0.016
T
MutationAssessor
Uncertain
2.6
M;.
PrimateAI
Benign
0.41
T
PROVEAN
Uncertain
-3.9
D;D
REVEL
Pathogenic
0.69
Sift
Uncertain
0.0020
D;D
Sift4G
Uncertain
0.060
T;T
Polyphen
0.98
D;D
Vest4
0.77
MutPred
0.80
Loss of methylation at K1440 (P = 0.036);.;
MVP
0.78
MPC
0.33
ClinPred
0.45
T
GERP RS
5.1
Varity_R
0.41
gMVP
0.47

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Pathogenic
0.99
dbscSNV1_RF
Pathogenic
0.73
SpliceAI score (max)
0.020
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: rs121912886; hg19: chr12-48367873; COSMIC: COSV61527816; COSMIC: COSV61527816; API