rs121912886

Positions:

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

Splicing: ADA: 0.9916

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]

COL2A1 links:

COL2A1 (HGNC:):

COL2A1 links:

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
COL2A1	NM_001844.5 linkuse as main transcript	c.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	UniProt
COL2A1	ENST00000380518.8 linkuse as main transcript	c.4316C>T	p.Thr1439Met	missense_variant, splice_region_variant	53/54	1	NM_001844.5	ENSP00000369889.3	P02458-2
COL2A1	ENST00000337299.7 linkuse as main transcript	c.4109C>T	p.Thr1370Met	missense_variant, splice_region_variant	52/53	1		ENSP00000338213.6	P02458-1
COL2A1	ENST00000493991.5 linkuse as main transcript	n.3402C>T		splice_region_variant, non_coding_transcript_exon_variant	36/37	2

Frequencies

GnomAD3 genomes

AF:

0.0000526

AC:

AN:

152184

Hom.:

Cov.:

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:

AN:

251026

Hom.:

AF XY:

0.0000958

AC XY:

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:

AN:

1461876

Hom.:

Cov.:

AF XY:

0.0000440

AC XY:

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:

AN:

152184

Hom.:

Cov.:

AF XY:

0.0000538

AC XY:

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.:

Bravo

AF:

0.0000907

ExAC

AF:

0.0000576

AC:

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 provided	literature only	OMIM	Nov 22, 2001	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Genomic Research Center, Shahid Beheshti University of Medical Sciences	Jan 01, 2019	- -

Spondyloperipheral dysplasia

Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Sep 15, 2014

The 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 provided

clinical testing

PreventionGenetics, part of Exact Sciences

Mar 15, 2024

The 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 submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jan 18, 2024

This 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

BayesDel_noAF

Uncertain

0.040

CADD

Pathogenic

DANN

Uncertain

1.0

DEOGEN2

Uncertain

0.79

D;.

Eigen

Uncertain

0.59

Eigen_PC

Uncertain

0.58

FATHMM_MKL

Uncertain

0.92

LIST_S2

Pathogenic

0.98

D;D

M_CAP

Benign

0.066

MetaRNN

Pathogenic

0.89

D;D

MetaSVM

Uncertain

-0.016

MutationAssessor

Uncertain

2.6

M;.

PrimateAI

Benign

0.41

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

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.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over