2-20005878-G-T

Variant names:

• chr2-20005878-G-T
• rs28939677
• NM_002381.5:c.656C>A

Variant summary

Our verdict is Likely pathogenic. The variant received 8 ACMG points: 8P and 0B. PM2 PP3_Strong PP5_Moderate

The NM_002381.5(MATN3):​c.656C>A​(p.Ala219Asp) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000206 in 1,457,050 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: MATN3 NM_002381.5 missense
• Clinical Significance: Pathogenic criteria provided, single submitter P:2 O:1
• Conservation: PhyloP100: 9.97
• Publications: 9 publications found

Genes affected

MATN3 (HGNC:6909): (matrilin 3) This gene encodes a member of von Willebrand factor A domain containing protein family. This family of proteins is thought to be involved in the formation of filamentous networks in the extracellular matrices of various tissues. This protein contains two von Willebrand factor A domains; it is present in the cartilage extracellular matrix and has a role in the development and homeostasis of cartilage and bone. Mutations in this gene result in multiple epiphyseal dysplasia. [provided by RefSeq, Jul 2008]

MATN3 Gene-Disease associations (from GenCC):

• multiple epiphyseal dysplasia type 5

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: G2P, Ambry Genetics, Orphanet, Labcorp Genetics (formerly Invitae)
• spondyloepimetaphyseal dysplasia, matrilin-3 type

  Inheritance: AR, Unknown Classification: SUPPORTIVE, LIMITED Submitted by: Orphanet, Labcorp Genetics (formerly Invitae), Ambry Genetics

ACMG classification

Our verdict: Likely_pathogenic. The variant received 8 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.988
• PP5: Variant 2-20005878-G-T is Pathogenic according to our data. Variant chr2-20005878-G-T is described in ClinVar as Pathogenic. ClinVar VariationId is 7543.Status of the report is criteria_provided_single_submitter, 1 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_002381.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MATN3	NM_002381.5	MANE Select	c.656C>A	p.Ala219Asp	missense	Exon 2 of 8	NP_002372.1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MATN3	ENST00000407540.8	TSL:1 MANE Select	c.656C>A	p.Ala219Asp	missense	Exon 2 of 8	ENSP00000383894.3
	MATN3	ENST00000421259.2	TSL:1	c.656C>A	p.Ala219Asp	missense	Exon 2 of 7	ENSP00000398753.2
	MATN3	ENST00000856777.1		c.656C>A	p.Ala219Asp	missense	Exon 2 of 8	ENSP00000526836.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000206 AC: 3 AN: 1457050 Hom.: 0 Cov.: 32 AF XY: 0.00000414 AC XY: 3 AN XY: 724376

⚠️ 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: 33392

American (AMR) AF: 0.00 AC: 0 AN: 43786

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26012

East Asian (EAS) AF: 0.00 AC: 0 AN: 39466

South Asian (SAS) AF: 0.00 AC: 0 AN: 85446

European-Finnish (FIN) AF: 0.0000188 AC: 1 AN: 53166

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

European-Non Finnish (NFE) AF: 0.00000180 AC: 2 AN: 1109794

Other (OTH) AF: 0.00 AC: 0 AN: 60222

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.0662318), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 33

Alfa AF: 0.0000630 Hom.: 0

Bravo AF: 0.00000378

ClinVar

ClinVar submissions as Germline

Significance: Pathogenic

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
1	-	-	Multiple epiphyseal dysplasia type 5 (1)
1	-	-	not provided (1)
-	-	-	Multiple epiphyseal dysplasia (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.47	D
BayesDel_noAF	Pathogenic	0.43
CADD	Pathogenic	26
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.79	D
Eigen	Pathogenic	0.97
Eigen_PC	Pathogenic	0.84
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.99	D
M_CAP	Uncertain	0.18	D
MetaRNN	Pathogenic	0.99	D
MetaSVM	Pathogenic	0.96	D
MutationAssessor	Pathogenic	4.5	H
PhyloP100		10
PrimateAI	Uncertain	0.71	T
PROVEAN	Pathogenic	-5.3	D
REVEL	Pathogenic	0.91
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0010	D
Polyphen		1.0	D
Vest4		0.97
MutPred		0.93		Gain of relative solvent accessibility (P = 0.09)
MVP		0.99
MPC		0.92
ClinPred		1.0	D
GERP RS		5.4
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.98
gMVP		0.97
Mutation Taster		=2/98	disease causing (ClinVar)

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: rs28939677; hg19: chr2-20205639;