NM_001852.4:c.2063G>A

Variant names:

• chr1-40301189-C-T
• NM_001852.4:c.2063G>A

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PM2 PP3

The NM_001852.4(COL9A2):​c.2063G>A​(p.Gly688Glu) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Synonymous variant affecting the same amino acid position (i.e. G688G) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 32)
• Consequence: COL9A2 NM_001852.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.10
• Publications: 0 publications found

Genes affected

COL9A2 (HGNC:2218): (collagen type IX alpha 2 chain) This gene encodes one of the three alpha chains of type IX collagen, the major collagen component of hyaline cartilage. Type IX collagen, a heterotrimeric molecule, is usually found in tissues containing type II collagen, a fibrillar collagen. This chain is unusual in that, unlike the other two type IX alpha chains, it contains a covalently attached glycosaminoglycan side chain. Mutations in this gene are associated with multiple epiphyseal dysplasia. [provided by RefSeq, Jul 2008]

COL9A2 Gene-Disease associations (from GenCC):

• epiphyseal dysplasia, multiple, 2

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae)
• Stickler syndrome, type 5

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics, Genomics England PanelApp, G2P
• multiple epiphyseal dysplasia due to collagen 9 anomaly

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• autosomal recessive Stickler syndrome

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• Stickler syndrome

  Inheritance: AR Classification: LIMITED Submitted by: ClinGen

ACMG classification

Our verdict: Uncertain_significance. The variant received 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.809

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001852.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	COL9A2	NM_001852.4	MANE Select	c.2063G>A	p.Gly688Glu	missense	Exon 32 of 32	NP_001843.1	Q14055

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	COL9A2	ENST00000372748.8	TSL:1 MANE Select	c.2063G>A	p.Gly688Glu	missense	Exon 32 of 32	ENSP00000361834.3	Q14055
	COL9A2	ENST00000482722.5	TSL:1	n.2366G>A		non_coding_transcript_exon	Exon 31 of 31
	COL9A2	ENST00000869268.1		c.2147G>A	p.Gly716Glu	missense	Exon 32 of 32	ENSP00000539327.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

ClinVar submissions

Significance: Uncertain significance

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
-	1	-	not provided (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.53
BayesDel_addAF	Pathogenic	0.28	D
BayesDel_noAF	Pathogenic	0.16
CADD	Pathogenic	26
DANN	Uncertain	1.0
DEOGEN2	Benign	0.14	T
Eigen	Pathogenic	0.79
Eigen_PC	Pathogenic	0.76
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Benign	0.75	T
M_CAP	Pathogenic	0.53	D
MetaRNN	Pathogenic	0.81	D
MetaSVM	Pathogenic	0.85	D
MutationAssessor	Uncertain	2.3	M
PhyloP100		7.1
PrimateAI	Pathogenic	0.83	D
PROVEAN	Uncertain	-4.1	D
REVEL	Pathogenic	0.72
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.63
MutPred		0.40		Loss of glycosylation at S685 (P = 0.1405)
MVP		0.94
MPC		1.1
ClinPred		1.0	D
GERP RS		5.5
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.77
gMVP		0.96
Mutation Taster		=27/73	disease causing

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

hg19: chr1-40766861;