chr1-40301389-C-A

Variant names:

Variant summary

Our verdict is Benign. The variant received -20 ACMG points: 0P and 20B. BP4_StrongBP6_Very_StrongBS1BS2

The NM_001852.4(COL9A2):c.1871-8G>T variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000536 in 1,604,886 control chromosomes in the GnomAD database, including 2 homozygotes. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Likely benign (★★).

Frequency

Genomes: 𝑓 0.00015 ( 2 hom., cov: 32)

Exomes 𝑓: 0.000043 ( 0 hom. )

Consequence

COL9A2
NM_001852.4 splice_region, intron

Scores

Splicing: ADA: 0.00001560

Clinical Significance

Likely benign criteria provided, multiple submitters, no conflicts B:5

Conservation

PhyloP100: -0.561

Publications

0 publications found

Variant links:

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: G2P, PanelApp Australia, Labcorp Genetics (formerly Invitae), Ambry Genetics, Genomics England PanelApp
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

COL9A2 links:

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Benign. The variant received -20 ACMG points.

BP4

Computational evidence support a benign effect (BayesDel_noAF=-0.87).

BP6

Variant 1-40301389-C-A is Benign according to our data. Variant chr1-40301389-C-A is described in ClinVar as Likely_benign. ClinVar VariationId is 258380.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

BS1

Variant frequency is greater than expected in population amr. GnomAd4 allele frequency = 0.000151 (23/152304) while in subpopulation AMR AF = 0.000915 (14/15308). AF 95% confidence interval is 0.000552. There are 2 homozygotes in GnomAd4. There are 2 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check.

BS2

High Homozygotes in GnomAd4 at 2 AR,AD gene

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
COL9A2	NM_001852.4 link	c.1871-8G>T		splice_region_variant, intron_variant	Intron 31 of 31	ENST00000372748.8	NP_001843.1	Q14055

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
COL9A2	ENST00000372748.8 link	c.1871-8G>T		splice_region_variant, intron_variant	Intron 31 of 31	1	NM_001852.4	ENSP00000361834.3		Q14055
COL9A2	ENST00000482722.5 link	n.2174-8G>T		splice_region_variant, intron_variant	Intron 30 of 30	1

Frequencies

GnomAD3 genomes

AF:

0.000105

AC:

AN:

152186

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.000916

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.000386

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.00

Gnomad OTH

AF:

0.00

GnomAD2 exomes

AF:

0.0000457

AC:

AN:

240756

AF XY:

0.0000610

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.0000925

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.000224

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00000914

Gnomad OTH exome

AF:

0.000347

GnomAD4 exome

AF:

0.0000434

AC:

AN:

1452582

Hom.:

Cov.:

AF XY:

0.0000360

AC XY:

AN XY:

721838

show subpopulations

African (AFR)

AF:

0.00

AC:

AN:

32982

American (AMR)

AF:

0.0000700

AC:

AN:

42860

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

25688

East Asian (EAS)

AF:

0.000126

AC:

AN:

39556

South Asian (SAS)

AF:

0.0000117

AC:

AN:

85408

European-Finnish (FIN)

AF:

0.00

AC:

AN:

53206

Middle Eastern (MID)

AF:

0.00

AC:

AN:

5718

European-Non Finnish (NFE)

AF:

0.00000181

AC:

AN:

1107250

Other (OTH)

AF:

0.000868

AC:

AN:

59914

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.463

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Exome Het

Variant carriers

<30

30-35

35-40

40-45

45-50

50-55

55-60

60-65

65-70

70-75

75-80

>80

Age

GnomAD4 genome

AF:

0.000151

AC:

AN:

152304

Hom.:

Cov.:

AF XY:

0.0000269

AC XY:

AN XY:

74464

show subpopulations

African (AFR)

AF:

0.00

AC:

AN:

41570

American (AMR)

AF:

0.000915

AC:

AN:

15308

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

3470

East Asian (EAS)

AF:

0.000387

AC:

AN:

5172

South Asian (SAS)

AF:

0.00

AC:

AN:

4832

European-Finnish (FIN)

AF:

0.00

AC:

AN:

10620

Middle Eastern (MID)

AF:

0.00

AC:

AN:

294

European-Non Finnish (NFE)

AF:

0.00

AC:

AN:

68014

Other (OTH)

AF:

0.00331

AC:

AN:

2112

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.518

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Genome Het

Variant carriers

<30

30-35

35-40

40-45

45-50

50-55

55-60

60-65

65-70

70-75

75-80

>80

Age

Alfa

AF:

0.0000434

Hom.:

Bravo

AF:

0.0000604

Asia WGS

AF:

0.0220

AC:

AN:

3478

ClinVar

Significance: Likely benign

Submissions summary: Benign:5

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not specified

Benign:2

Dec 22, 2023

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Significance:Likely benign

Review Status:criteria provided, single submitter

Collection Method:clinical testing

Variant summary: COL9A2 c.1871-8G>T alters a non-conserved nucleotide located close to a canonical splice site and therefore could affect mRNA splicing, leading to a significantly altered protein sequence. Consensus agreement among computation tools predict no significant impact on normal splicing. However, these predictions have yet to be confirmed by functional studies. The variant allele was found at a frequency of 4.6e-05 in 240756 control chromosomes. To our knowledge, no occurrence of c.1871-8G>T in individuals affected with Epiphyseal dysplasia, multiple, 2 and no experimental evidence demonstrating its impact on protein function have been reported. Three submitters have cited clinical-significance assessments for this variant to ClinVar after 2014. All submitters classified the variant as likely benign. Based on the evidence outlined above, the variant was classified as likely benign. -

PreventionGenetics, part of Exact Sciences

Significance:Likely benign

Review Status:criteria provided, single submitter

Collection Method:clinical testing

- -

not provided

Benign:2

Mar 04, 2020

GeneDx

Significance:Likely benign

Review Status:criteria provided, single submitter

Collection Method:clinical testing

- -

Jan 23, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance:Likely benign

Review Status:criteria provided, single submitter

Collection Method:clinical testing

- -

Epiphyseal dysplasia, multiple, 2;C3280342:Stickler syndrome, type 5

Benign:1

Nov 16, 2021

Fulgent Genetics, Fulgent Genetics

Significance:Likely benign

Review Status:criteria provided, single submitter

Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_noAF

Benign

-0.87

CADD

Benign

1.2

(source)

DANN

Benign

0.44

PhyloP100

-0.56

Splicing

Name

Calibrated prediction

Score

Prediction

dbscSNV1_ADA

Benign

0.000016

dbscSNV1_RF

Benign

0.0

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

You must be logged in to view publications. This limit was set because tens of millions (!) of queries from AI bots are generated daily.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

Publications

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

Age Distribution

Age Distribution

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

Other links and lift over