rs1450980907

Variant names:

• chr11-44126950-G-A
• rs1450980907
• NM_207122.2:c.1074G>A

Your query was ambiguous. Multiple possible variants found:

• chr11-44126950-G-A
• chr11-44126950-G-T

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 12P and 0B. PVS1 PM2 PP5_Moderate

The NM_207122.2(EXT2):​c.1074G>A​(p.Trp358*) variant causes a stop gained change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★). Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 33)
• Consequence: EXT2 NM_207122.2 stop_gained
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 9.86
• Publications: 1 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: Genomics England PanelApp, Labcorp Genetics (formerly Invitae), ClinGen, Ambry Genetics, G2P
• seizures-scoliosis-macrocephaly syndrome

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

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 12 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 11-44126950-G-A is Pathogenic according to our data. Variant chr11-44126950-G-A is described in ClinVar as Pathogenic. ClinVar VariationId is 534139.Status of the report is criteria_provided_single_submitter, 1 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

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	EXT2	NM_207122.2	MANE Select	c.1074G>A	p.Trp358*	stop_gained	Exon 6 of 14	NP_997005.1
	EXT2	NM_000401.3		c.1173G>A	p.Trp391*	stop_gained	Exon 6 of 14	NP_000392.3
	EXT2	NM_001178083.3		c.1074G>A	p.Trp358*	stop_gained	Exon 6 of 15	NP_001171554.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	EXT2	ENST00000533608.7	TSL:1 MANE Select	c.1074G>A	p.Trp358*	stop_gained	Exon 6 of 14	ENSP00000431173.2
	EXT2	ENST00000358681.8	TSL:1	c.1074G>A	p.Trp358*	stop_gained	Exon 6 of 15	ENSP00000351509.4
	EXT2	ENST00000343631.4	TSL:1	c.1074G>A	p.Trp358*	stop_gained	Exon 7 of 15	ENSP00000342656.3

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 33

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Exostoses, multiple, type 2 Pathogenic:1

Mar 17, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change creates a premature translational stop signal (p.Trp358*) in the EXT2 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in EXT2 are known to be pathogenic (PMID: 10679937, 19810120). This variant is not present in population databases (gnomAD no frequency). This premature translational stop signal has been observed in individual(s) with multiple osteochondromas (PMID: 19810120, 23439489). ClinVar contains an entry for this variant (Variation ID: 534139). For these reasons, this variant has been classified as Pathogenic.

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.66
CADD	Pathogenic	44
DANN	Uncertain	1.0
Eigen	Pathogenic	1.0
Eigen_PC	Pathogenic	0.95
FATHMM_MKL	Pathogenic	1.0	D
PhyloP100		9.9
Vest4		0.89
GERP RS		5.7
Mutation Taster		=0/200	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: rs1450980907; hg19: chr11-44148500;