rs886041272

Variant names:

• chr11-44108109-C-CTGCT
• rs886041272
• NM_207122.2:c.398_401dupTGCT

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_207122.2(EXT2):​c.398_401dupTGCT​(p.Met135AlafsTer8) variant causes a frameshift change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 32)
• Consequence: EXT2 NM_207122.2 frameshift
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:2
• Conservation: PhyloP100: 7.91
• Publications: 0 publications found

Genes affected

EXT2 (HGNC:3513): (exostosin glycosyltransferase 2) This gene encodes one of two glycosyltransferases involved in the chain elongation step of heparan sulfate biosynthesis. Mutations in this gene cause the type II form of multiple exostoses. Alternatively spliced transcript variants encoding different isoforms have been noted for this gene. [provided by RefSeq, Jul 2008]

EXT2 Gene-Disease associations (from GenCC):

• exostoses, multiple, type 2

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: G2P, Ambry Genetics, Labcorp Genetics (formerly Invitae), ClinGen, Genomics England PanelApp
• seizures-scoliosis-macrocephaly syndrome

  Inheritance: AR Classification: STRONG, SUPPORTIVE, LIMITED Submitted by: Orphanet, Ambry Genetics, Labcorp Genetics (formerly Invitae)
• hereditary multiple osteochondromas

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 18 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 11-44108109-C-CTGCT is Pathogenic according to our data. Variant chr11-44108109-C-CTGCT is described in ClinVar as Pathogenic. ClinVar VariationId is 279944.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_207122.2. 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
	EXT2	NM_207122.2	MANE Select	c.398_401dupTGCT	p.Met135AlafsTer8	frameshift	Exon 2 of 14	NP_997005.1	Q93063-1
	EXT2	NM_000401.3		c.497_500dupTGCT	p.Met168AlafsTer8	frameshift	Exon 2 of 14	NP_000392.3	Q93063-3
	EXT2	NM_001178083.3		c.398_401dupTGCT	p.Met135AlafsTer8	frameshift	Exon 2 of 15	NP_001171554.1	Q93063-2

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	EXT2	ENST00000533608.7	TSL:1 MANE Select	c.398_401dupTGCT	p.Met135AlafsTer8	frameshift	Exon 2 of 14	ENSP00000431173.2	Q93063-1
	EXT2	ENST00000358681.8	TSL:1	c.398_401dupTGCT	p.Met135AlafsTer8	frameshift	Exon 2 of 15	ENSP00000351509.4	Q93063-2
	EXT2	ENST00000343631.4	TSL:1	c.398_401dupTGCT	p.Met135AlafsTer8	frameshift	Exon 3 of 15	ENSP00000342656.3	Q93063-1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

ClinVar submissions as Germline

Significance: Pathogenic

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
1	-	-	Exostoses, multiple, type 2 (1)
1	-	-	not provided (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
PhyloP100		7.9
Mutation Taster		=0/200	disease causing (ClinVar)

Splicing

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

Other links and lift over

dbSNP: rs886041272; hg19: chr11-44129659;