11-44109201-C-T

Variant names:

• chr11-44109201-C-T
• rs886039358
• NM_207122.2:c.544C>T

Variant summary

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

The NM_000401.3(EXT2):​c.643C>T​(p.Arg215*) variant causes a stop gained change. The variant allele was found at a frequency of 0.00000248 in 1,613,850 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 (★★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: EXT2 NM_000401.3 stop_gained
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:6
• Conservation: PhyloP100: 4.00
• Publications: 12 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 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 11-44109201-C-T is Pathogenic according to our data. Variant chr11-44109201-C-T is described in ClinVar as Pathogenic. ClinVar VariationId is 265133.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000401.3. 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.544C>T	p.Arg182*	stop_gained	Exon 3 of 14	NP_997005.1
	EXT2	NM_000401.3		c.643C>T	p.Arg215*	stop_gained	Exon 3 of 14	NP_000392.3
	EXT2	NM_001178083.3		c.544C>T	p.Arg182*	stop_gained	Exon 3 of 15	NP_001171554.1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	EXT2	ENST00000533608.7	TSL:1 MANE Select	c.544C>T	p.Arg182*	stop_gained	Exon 3 of 14	ENSP00000431173.2
	EXT2	ENST00000358681.8	TSL:1	c.544C>T	p.Arg182*	stop_gained	Exon 3 of 15	ENSP00000351509.4
	EXT2	ENST00000343631.4	TSL:1	c.544C>T	p.Arg182*	stop_gained	Exon 4 of 15	ENSP00000342656.3

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152114 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.000208

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1461736 Hom.: 0 Cov.: 31 AF XY: 0.00000275 AC XY: 2 AN XY: 727184

African (AFR) AF: 0.0000299 AC: 1 AN: 33472

American (AMR) AF: 0.00 AC: 0 AN: 44722

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26132

East Asian (EAS) AF: 0.00 AC: 0 AN: 39692

South Asian (SAS) AF: 0.00 AC: 0 AN: 86252

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53412

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

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1111896

Other (OTH) AF: 0.0000166 AC: 1 AN: 60392

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152114 Hom.: 0 Cov.: 32 AF XY: 0.0000135 AC XY: 1 AN XY: 74308

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

African (AFR) AF: 0.00 AC: 0 AN: 41424

American (AMR) AF: 0.00 AC: 0 AN: 15270

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3468

East Asian (EAS) AF: 0.00 AC: 0 AN: 5194

South Asian (SAS) AF: 0.000208 AC: 1 AN: 4816

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10608

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 68022

Other (OTH) AF: 0.00 AC: 0 AN: 2084

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

Alfa AF: 0.00 Hom.: 0

ClinVar

ClinVar submissions as Germline

Significance: Pathogenic

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
3	-	-	Exostoses, multiple, type 2 (3)
2	-	-	not provided (2)
1	-	-	Exostoses, multiple, type 2;C4225248:Seizures-scoliosis-macrocephaly syndrome (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.63
CADD	Pathogenic	39
DANN	Uncertain	1.0
Eigen	Pathogenic	0.75
Eigen_PC	Uncertain	0.61
FATHMM_MKL	Uncertain	0.94	D
PhyloP100		4.0
Vest4		0.89
GERP RS		4.6
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Mutation Taster		=0/200	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
Splicevardb		2.0
SpliceAI score (max)		0.020		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: rs886039358; hg19: chr11-44130751; COSMIC: COSV59148031; COSMIC: COSV59148031;