20-62826839-G-T

Variant names:

• chr20-62826839-G-T
• rs115466848
• NM_001853.4:c.792+19G>T

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_001853.4(COL9A3):​c.792+19G>T variant causes a intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000205 in 1,459,958 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: COL9A3 NM_001853.4 intron
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 0.356
• 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: Ambry Genetics, Illumina, G2P, Labcorp Genetics (formerly Invitae)
• Stickler syndrome

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

  Inheritance: AR Classification: DEFINITIVE, STRONG, LIMITED Submitted by: G2P, Ambry Genetics, Labcorp Genetics (formerly Invitae)
• 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: Likely_benign. The variant received -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.91).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
COL9A3	NM_001853.4	c.792+19G>T		intron_variant	Intron 15 of 31	ENST00000649368.1	NP_001844.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
COL9A3	ENST00000649368.1	c.792+19G>T		intron_variant	Intron 15 of 31		NM_001853.4	ENSP00000496793.1
COL9A3	ENST00000463487.2	n.500+19G>T		intron_variant	Intron 7 of 10	5
COL9A3	ENST00000489045.5	n.*19G>T		downstream_gene_variant		5

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1459958 Hom.: 0 Cov.: 32 AF XY: 0.00000138 AC XY: 1 AN XY: 726296

African (AFR) AF: 0.00 AC: 0 AN: 33470

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

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26124

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

South Asian (SAS) AF: 0.00 AC: 0 AN: 86214

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 51862

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5766

European-Non Finnish (NFE) AF: 0.00000270 AC: 3 AN: 1111796

Other (OTH) AF: 0.00 AC: 0 AN: 60338

GnomAD4 genome Cov.: 33

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.91
CADD	Benign	3.6
DANN	Benign	0.31
PhyloP100		0.36
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1

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

dbSNP: rs115466848; hg19: chr20-61458191;