chr6-33178127-C-T

Variant names:

• chr6-33178127-C-T
• rs727504891
• NM_080680.3:c.1872+5G>A

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM2 PP3_Strong

The NM_080680.3(COL11A2):​c.1872+5G>A variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000687 in 1,455,968 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: COL11A2 NM_080680.3 splice_region, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: 2.64
• Publications: 0 publications found

Genes affected

COL11A2 (HGNC:2187): (collagen type XI alpha 2 chain) This gene encodes one of the two alpha chains of type XI collagen, a minor fibrillar collagen. It is located on chromosome 6 very close to but separate from the gene for retinoid X receptor beta. Type XI collagen is a heterotrimer but the third alpha chain is a post-translationally modified alpha 1 type II chain. Proteolytic processing of this type XI chain produces PARP, a proline/arginine-rich protein that is an amino terminal domain. Mutations in this gene are associated with type III Stickler syndrome, otospondylomegaepiphyseal dysplasia (OSMED syndrome), Weissenbacher-Zweymuller syndrome, autosomal dominant non-syndromic sensorineural type 13 deafness (DFNA13), and autosomal recessive non-syndromic sensorineural type 53 deafness (DFNB53). Alternative splicing results in multiple transcript variants. A related pseudogene is located nearby on chromosome 6. [provided by RefSeq, Jul 2009]

COL11A2 Gene-Disease associations (from GenCC):

• autosomal dominant nonsyndromic hearing loss 13

  Inheritance: AD Classification: DEFINITIVE, STRONG, MODERATE, LIMITED Submitted by: Ambry Genetics, PanelApp Australia, Labcorp Genetics (formerly Invitae), G2P
• nonsyndromic genetic hearing loss

  Inheritance: AD, AR Classification: DEFINITIVE, MODERATE Submitted by: ClinGen
• otospondylomegaepiphyseal dysplasia, autosomal dominant

  Inheritance: AD Classification: DEFINITIVE, STRONG, MODERATE, SUPPORTIVE Submitted by: PanelApp Australia, Ambry Genetics, Orphanet, Genomics England PanelApp, Labcorp Genetics (formerly Invitae), G2P
• autosomal recessive nonsyndromic hearing loss 53

  Inheritance: AR Classification: DEFINITIVE, STRONG, MODERATE Submitted by: G2P, PanelApp Australia, Ambry Genetics, Labcorp Genetics (formerly Invitae)
• otospondylomegaepiphyseal dysplasia

  Inheritance: AR, AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: Orphanet, ClinGen
• otospondylomegaepiphyseal dysplasia, autosomal recessive

  Inheritance: AR Classification: DEFINITIVE, STRONG, MODERATE Submitted by: PanelApp Australia, Ambry Genetics, G2P, Labcorp Genetics (formerly Invitae)
• autosomal dominant nonsyndromic hearing loss

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• fibrochondrogenesis

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• hearing loss, autosomal recessive

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF, max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
COL11A2	NM_080680.3	c.1872+5G>A		splice_region_variant, intron_variant	Intron 21 of 65	ENST00000341947.7	NP_542411.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
COL11A2	ENST00000341947.7	c.1872+5G>A		splice_region_variant, intron_variant	Intron 21 of 65	5	NM_080680.3	ENSP00000339915.2
COL11A2	ENST00000374708.8	c.1614+5G>A		splice_region_variant, intron_variant	Intron 19 of 63	5		ENSP00000363840.4
COL11A2	ENST00000361917.6	c.444+181G>A		intron_variant	Intron 8 of 23	5		ENSP00000355123.2
COL11A2	ENST00000477772.1	n.-234G>A		upstream_gene_variant		2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.87e-7 AC: 1 AN: 1455968 Hom.: 0 Cov.: 34 AF XY: 0.00000138 AC XY: 1 AN XY: 723652

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 33420

American (AMR) AF: 0.00 AC: 0 AN: 44452

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25772

East Asian (EAS) AF: 0.00 AC: 0 AN: 39606

South Asian (SAS) AF: 0.00 AC: 0 AN: 85632

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 52220

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5740

European-Non Finnish (NFE) AF: 9.02e-7 AC: 1 AN: 1108968

Other (OTH) AF: 0.00 AC: 0 AN: 60158

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.000000), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Uncertain:2

Aug 25, 2023

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Has not been previously published as pathogenic or benign to our knowledge; Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports a deleterious effect on splicing -

Nov 15, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change falls in intron 21 of the COL11A2 gene. It does not directly change the encoded amino acid sequence of the COL11A2 protein. It affects a nucleotide within the consensus splice site. This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with COL11A2-related conditions. ClinVar contains an entry for this variant (Variation ID: 179480). Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. 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. -

not specified Uncertain:1

Apr 11, 2014

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Variant classified as Uncertain Significance - Favor Pathogenic. The 1872+5G>A v ariant in the 5' splice region of COL11A2 has been identified by our laboratory in one proband with hearing loss and also segregated with the hearing loss in tw o affected family members (LMM-unpublished data). It has not been identified in large population studies. Computational tools suggest an impact to splicing, tho ugh this information is not predictive enough to determine pathogenicity. In sum mary, the clinical significance of this variant cannot be determined with certai nty; however, based upon the possible impact on splicing and the segregation dat a, we lean towards a more likely pathogenic role. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.31
CADD	Pathogenic	27
DANN	Benign	0.91
PhyloP100		2.6

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	1.0
SpliceAI score (max)		0.91		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.58		Position offset: -25
DS_DL_spliceai		0.91		Position offset: 5

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

Other links and lift over

dbSNP: rs727504891; hg19: chr6-33145904;