chr6-70216723-A-T

Variant names:

• chr6-70216723-A-T
• rs776515044
• NM_001851.6:c.*174T>A

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_001851.6(COL9A1):​c.*174T>A variant causes a 3 prime UTR change. The variant allele was found at a frequency of 0.00000183 in 546,860 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: 32)
  • Exomes 𝑓: 0.0000018 (0 hom.)
• Consequence: COL9A1 NM_001851.6 3_prime_UTR
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 5.08
• Publications: 0 publications found

Genes affected

COL9A1 (HGNC:2217): (collagen type IX alpha 1 chain) This gene encodes one of the three alpha chains of type IX collagen, which is a minor (5-20%) collagen component of hyaline cartilage. Type IX collagen is usually found in tissues containing type II collagen, a fibrillar collagen. Studies in knockout mice have shown that synthesis of the alpha 1 chain is essential for assembly of type IX collagen molecules, a heterotrimeric molecule, and that lack of type IX collagen is associated with early onset osteoarthritis. Mutations in this gene are associated with osteoarthritis in humans, with multiple epiphyseal dysplasia, 6, a form of chondrodysplasia, and with Stickler syndrome, a disease characterized by ophthalmic, orofacial, articular, and auditory defects. Two transcript variants that encode different isoforms have been identified for this gene. [provided by RefSeq, Jul 2008]

COL9A1 Gene-Disease associations (from GenCC):

• epiphyseal dysplasia, multiple, 6

  Inheritance: AD, AR, Unknown Classification: DEFINITIVE, LIMITED Submitted by: G2P, Ambry Genetics, Labcorp Genetics (formerly Invitae)
• Stickler syndrome, type 4

  Inheritance: AR Classification: DEFINITIVE, STRONG, MODERATE Submitted by: Ambry Genetics, G2P, Genomics England PanelApp, PanelApp Australia, 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
• Stickler syndrome

  Inheritance: AR Classification: LIMITED Submitted by: ClinGen

ACMG classification

Our verdict: Uncertain_significance. The variant received 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.3).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
COL9A1	NM_001851.6	c.*174T>A		3_prime_UTR_variant	Exon 38 of 38	ENST00000357250.11	NP_001842.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
COL9A1	ENST00000357250.11	c.*174T>A		3_prime_UTR_variant	Exon 38 of 38	1	NM_001851.6	ENSP00000349790.6

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000183 AC: 1 AN: 546860 Hom.: 0 Cov.: 6 AF XY: 0.00 AC XY: 0 AN XY: 287994

African (AFR) AF: 0.00 AC: 0 AN: 15186

American (AMR) AF: 0.00 AC: 0 AN: 31414

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 17452

East Asian (EAS) AF: 0.00 AC: 0 AN: 31356

South Asian (SAS) AF: 0.00 AC: 0 AN: 55400

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 43610

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 2276

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 320858

Other (OTH) AF: 0.0000341 AC: 1 AN: 29308

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.30
CADD	Benign	17
DANN	Benign	0.87
PhyloP100		5.1

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: rs776515044; hg19: chr6-70926426;