chr20-62836196-C-G

Variant names:

• chr20-62836196-C-G
• rs747896279
• NM_001853.4:c.1411C>G

Variant summary

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

The NM_001853.4(COL9A3):​c.1411C>G​(p.Arg471Gly) 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 1,460,964 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 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. R471L) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: COL9A3 NM_001853.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 2.47
• Publications: 0 publications found

Genes affected

COL9A3 (HGNC:2219): (collagen type IX alpha 3 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. Mutations in this gene are associated with multiple epiphyseal dysplasia type 3. [provided by RefSeq, Jan 2010]

COL9A3 Gene-Disease associations (from GenCC):

• epiphyseal dysplasia, multiple, 3

  Inheritance: AD Classification: DEFINITIVE, STRONG, MODERATE Submitted by: Illumina, Labcorp Genetics (formerly Invitae), Ambry Genetics, G2P
• Stickler syndrome

  Inheritance: AR Classification: DEFINITIVE, STRONG, LIMITED Submitted by: ClinGen, Ambry Genetics, Genomics England PanelApp
• Stickler syndrome, type 6

  Inheritance: AR Classification: DEFINITIVE, STRONG, LIMITED Submitted by: G2P, Labcorp Genetics (formerly Invitae), Ambry Genetics
• 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

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, 0.776

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001853.4. 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
	COL9A3	NM_001853.4	MANE Select	c.1411C>G	p.Arg471Gly	missense	Exon 28 of 32	NP_001844.3

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	COL9A3	ENST00000649368.1	MANE Select	c.1411C>G	p.Arg471Gly	missense	Exon 28 of 32	ENSP00000496793.1	Q14050
	COL9A3	ENST00000934236.1		c.1462C>G	p.Arg488Gly	missense	Exon 29 of 33	ENSP00000604295.1
	COL9A3	ENST00000894732.1		c.1339C>G	p.Arg447Gly	missense	Exon 27 of 31	ENSP00000564791.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1460964 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 726798

African (AFR) AF: 0.00 AC: 0 AN: 33476

American (AMR) AF: 0.00 AC: 0 AN: 44694

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26116

East Asian (EAS) AF: 0.00 AC: 0 AN: 39694

South Asian (SAS) AF: 0.00 AC: 0 AN: 86226

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 52736

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5764

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1111906

Other (OTH) AF: 0.00 AC: 0 AN: 60352

GnomAD4 genome Cov.: 33

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	Benign	0.16
BayesDel_addAF	Pathogenic	0.26	D
BayesDel_noAF	Pathogenic	0.14
CADD	Uncertain	24
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.48	T
Eigen	Uncertain	0.45
Eigen_PC	Uncertain	0.36
FATHMM_MKL	Uncertain	0.84	D
LIST_S2	Uncertain	0.90	D
M_CAP	Pathogenic	0.38	D
MetaRNN	Pathogenic	0.78	D
MetaSVM	Pathogenic	0.83	D
MutationAssessor	Benign	1.3	L
PhyloP100		2.5
PrimateAI	Uncertain	0.51	T
PROVEAN	Uncertain	-2.8	D
REVEL	Pathogenic	0.66
Sift	Uncertain	0.021	D
Sift4G	Benign	0.067	T
Polyphen		1.0	D
Vest4		0.68
MutPred		0.49		Loss of methylation at R471 (P = 0.009)
MVP		0.89
MPC		0.47
ClinPred		0.98	D
GERP RS		3.6
Varity_R		0.22
gMVP		0.71
Mutation Taster		=85/15	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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

dbSNP: rs747896279; hg19: chr20-61467548;