rs1555164786

chr12-47975568-C-G

Variant summary

Our verdict is Likely pathogenic. Variant got 9 ACMG points: 9P and 0B. PM1 PM2 PP2 PP3_Strong

The NM_001844.5(COL2A1):c.3635G>C(p.Gly1212Ala) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 12/21 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 33)
• Consequence: COL2A1 NM_001844.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.91

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]

ACMG classification

Verdict is Likely_pathogenic. Variant got 9 ACMG points.

• PM1: In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 2 benign, 7 uncertain in NM_001844.5
• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant where missense usually causes diseases, COL2A1
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.991

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
COL2A1	NM_001844.5	c.3635G>C	p.Gly1212Ala	missense_variant	51/54	ENST00000380518.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
COL2A1	ENST00000380518.8	c.3635G>C	p.Gly1212Ala	missense_variant	51/54	1	NM_001844.5	P1
COL2A1	ENST00000337299.7	c.3428G>C	p.Gly1143Ala	missense_variant	50/53	1
COL2A1	ENST00000546974.1	n.488G>C		non_coding_transcript_exon_variant	6/6	1
COL2A1	ENST00000493991.5	n.2721G>C		non_coding_transcript_exon_variant	34/37	2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Stickler syndrome type 1 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Center for Human Genetics, Inc, Center for Human Genetics, Inc

Nov 01, 2016

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.83
BayesDel_addAF	Pathogenic	0.56	D
BayesDel_noAF	Pathogenic	0.57
Cadd	Pathogenic	26
Dann	Uncertain	1.0
DEOGEN2	Pathogenic	0.95	D;.
Eigen	Pathogenic	0.88
Eigen_PC	Pathogenic	0.80
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.98	D;D
M_CAP	Pathogenic	0.90	D
MetaRNN	Pathogenic	0.99	D;D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Pathogenic	3.7	H;.
MutationTaster	Benign	1.0	D;D
PrimateAI	Pathogenic	0.94	D
PROVEAN	Pathogenic	-5.6	D;D
REVEL	Pathogenic	0.97
Sift	Uncertain	0.015	D;D
Sift4G	Pathogenic	0.0	D;D
Polyphen		1.0	D;D
Vest4		0.92
MutPred		0.98		Loss of catalytic residue at G1212 (P = 0.1238);.;
MVP		0.97
MPC		0.34
ClinPred		1.0	D
GERP RS		4.7
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.6
Varity_R		0.89
gMVP		0.98

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

Other links and lift over

dbSNP: rs1555164786; hg19: chr12-48369351;