8-117835473-C-T

Variant summary

Our verdict is Benign. The variant received -7 ACMG points: 0P and 7B. BP4_ModerateBP6BS2

The NM_000127.3(EXT1):​c.1135G>A​(p.Val379Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000279 in 1,613,976 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. V379F) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000029 ( 0 hom. )

Consequence

EXT1
NM_000127.3 missense

Scores

6
13

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1B:1O:1

Conservation

PhyloP100: 2.25

Publications

3 publications found
Variant links:
Genes affected
EXT1 (HGNC:3512): (exostosin glycosyltransferase 1) This gene encodes an endoplasmic reticulum-resident type II transmembrane glycosyltransferase involved in the chain elongation step of heparan sulfate biosynthesis. Mutations in this gene cause the type I form of multiple exostoses. [provided by RefSeq, Jul 2008]
EXT1 Gene-Disease associations (from GenCC):
  • exostoses, multiple, type 1
    Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P, ClinGen
  • chondrosarcoma
    Inheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp
  • hereditary multiple osteochondromas
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Benign. The variant received -7 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.16815224).
BP6
Variant 8-117835473-C-T is Benign according to our data. Variant chr8-117835473-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 134199.
BS2
High AC in GnomAdExome4 at 42 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
EXT1NM_000127.3 linkc.1135G>A p.Val379Ile missense_variant Exon 3 of 11 ENST00000378204.7 NP_000118.2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
EXT1ENST00000378204.7 linkc.1135G>A p.Val379Ile missense_variant Exon 3 of 11 1 NM_000127.3 ENSP00000367446.3

Frequencies

GnomAD3 genomes
AF:
0.0000197
AC:
3
AN:
152174
Hom.:
0
Cov.:
32
show subpopulations
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:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000441
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000159
AC:
4
AN:
251168
AF XY:
0.0000147
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.0000544
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000264
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000287
AC:
42
AN:
1461802
Hom.:
0
Cov.:
31
AF XY:
0.0000289
AC XY:
21
AN XY:
727206
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.000151
AC:
6
AN:
39696
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53416
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000279
AC:
31
AN:
1111936
Other (OTH)
AF:
0.0000828
AC:
5
AN:
60388
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.476
Heterozygous variant carriers
0
3
6
10
13
16
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000197
AC:
3
AN:
152174
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74344
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41432
American (AMR)
AF:
0.00
AC:
0
AN:
15280
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5188
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4828
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10616
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000441
AC:
3
AN:
68036
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.0000264
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.0000330
AC:
4

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:1Benign:1Other:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Chondrosarcoma Uncertain:1
Oct 12, 2023
Baylor Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Multiple congenital exostosis Benign:1
Jan 27, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not specified Other:1
Sep 19, 2013
ITMI
Significance:not provided
Review Status:no classification provided
Collection Method:reference population

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.065
BayesDel_addAF
Benign
-0.022
T
BayesDel_noAF
Benign
-0.10
CADD
Benign
19
DANN
Benign
0.43
DEOGEN2
Uncertain
0.66
D
Eigen
Benign
-0.46
Eigen_PC
Benign
-0.21
FATHMM_MKL
Uncertain
0.88
D
LIST_S2
Uncertain
0.89
D
M_CAP
Benign
0.049
D
MetaRNN
Benign
0.17
T
MetaSVM
Uncertain
0.35
D
MutationAssessor
Benign
-0.23
N
PhyloP100
2.3
PrimateAI
Uncertain
0.56
T
PROVEAN
Benign
0.37
N
REVEL
Uncertain
0.43
Sift
Benign
1.0
T
Sift4G
Benign
1.0
T
Polyphen
0.0040
B
Vest4
0.16
MVP
0.35
MPC
0.33
ClinPred
0.16
T
GERP RS
3.6
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.036
gMVP
0.48
Mutation Taster
=93/7
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
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

Publications

Other links and lift over

dbSNP: rs371233961; hg19: chr8-118847712; COSMIC: COSV105929318; API