chr20-62817090-C-CGCTCCT

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2PM4

The NM_001853.4(COL9A3):​c.43_48dup​(p.Leu15_Leu16dup) variant causes a inframe insertion change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000502 in 1,394,654 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★). Synonymous variant affecting the same amino acid position (i.e. P9P) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000053 ( 0 hom. )

Consequence

COL9A3
NM_001853.4 inframe_insertion

Scores

Not classified

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: -0.107
Variant links:
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 4 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PM4
Nonframeshift variant in NON repetitive region in NM_001853.4.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE UniProt
COL9A3NM_001853.4 linkuse as main transcriptc.43_48dup p.Leu15_Leu16dup inframe_insertion 1/32 ENST00000649368.1

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Appris UniProt
COL9A3ENST00000649368.1 linkuse as main transcriptc.43_48dup p.Leu15_Leu16dup inframe_insertion 1/32 NM_001853.4 P1
COL9A3ENST00000477612.5 linkuse as main transcriptn.75-460_75-455dup intron_variant, non_coding_transcript_variant 3

Frequencies

GnomAD3 genomes
AF:
0.0000264
AC:
4
AN:
151322
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000242
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000132
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.0000973
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000123
AC:
1
AN:
81068
Hom.:
0
AF XY:
0.0000213
AC XY:
1
AN XY:
46948
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.0000610
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000531
AC:
66
AN:
1243332
Hom.:
0
Cov.:
30
AF XY:
0.0000522
AC XY:
32
AN XY:
613174
show subpopulations
Gnomad4 AFR exome
AF:
0.0000799
Gnomad4 AMR exome
AF:
0.0000825
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.0000816
Gnomad4 SAS exome
AF:
0.0000609
Gnomad4 FIN exome
AF:
0.0000335
Gnomad4 NFE exome
AF:
0.0000500
Gnomad4 OTH exome
AF:
0.000101
GnomAD4 genome
AF:
0.0000264
AC:
4
AN:
151322
Hom.:
0
Cov.:
33
AF XY:
0.0000406
AC XY:
3
AN XY:
73880
show subpopulations
Gnomad4 AFR
AF:
0.0000242
Gnomad4 AMR
AF:
0.000132
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.0000973
Gnomad4 NFE
AF:
0.00
Gnomad4 OTH
AF:
0.00

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Uncertain:2
Uncertain significance, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpOct 27, 2023This variant, c.43_48dup, results in the insertion of 2 amino acid(s) of the COL9A3 protein (p.Leu15_Leu16dup), but otherwise preserves the integrity of the reading frame. This variant is present in population databases (no rsID available, gnomAD 0.01%). This variant has not been reported in the literature in individuals affected with COL9A3-related conditions. ClinVar contains an entry for this variant (Variation ID: 1422320). Experimental studies and prediction algorithms are not available or were not evaluated, and the functional significance of this variant is currently unknown. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -
Uncertain significance, criteria provided, single submitterclinical testingGeneDxDec 19, 2023Not observed at significant frequency in large population cohorts (gnomAD); In-frame insertion of 2 amino acids in a non-repeat region; Has not been previously published as pathogenic or benign to our knowledge -
COL9A3-related disorder Uncertain:1
Uncertain significance, no assertion criteria providedclinical testingPreventionGenetics, part of Exact SciencesJan 22, 2024The COL9A3 c.43_48dup6 variant is predicted to result in an in-frame duplication (p.Leu15_Leu16dup). To our knowledge, this variant has not been reported in the literature. This variant is reported in 0.013% of alleles in individuals of European (Finnish) descent in gnomAD. At this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction

Splicing

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs1036479876; hg19: chr20-61448442; API