chr11-44107723-C-T

Variant summary

Our verdict is Likely benign. The variant received -6 ACMG points: 0P and 6B. BP4_ModerateBS2

The NM_207122.2(EXT2):​c.11C>T​(p.Ser4Leu) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000378 in 1,614,140 control chromosomes in the GnomAD database, including 2 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. S4S) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000039 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000038 ( 2 hom. )

Consequence

EXT2
NM_207122.2 missense

Scores

1
6
12

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:2U:2B:1

Conservation

PhyloP100: 7.46

Publications

6 publications found
Variant links:
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

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -6 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.1664857).
BS2
High Homozygotes in GnomAdExome4 at 2 AD,AR gene

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
EXT2NM_207122.2 linkc.11C>T p.Ser4Leu missense_variant Exon 2 of 14 ENST00000533608.7 NP_997005.1 Q93063-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
EXT2ENST00000533608.7 linkc.11C>T p.Ser4Leu missense_variant Exon 2 of 14 1 NM_207122.2 ENSP00000431173.2 Q93063-1

Frequencies

GnomAD3 genomes
AF:
0.0000329
AC:
5
AN:
152172
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:
0.000207
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00316
Gnomad NFE
AF:
0.0000441
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000637
AC:
16
AN:
251294
AF XY:
0.0000442
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000868
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.0000463
Gnomad NFE exome
AF:
0.0000264
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000376
AC:
55
AN:
1461850
Hom.:
2
Cov.:
32
AF XY:
0.0000426
AC XY:
31
AN XY:
727222
show subpopulations
African (AFR)
AF:
0.0000299
AC:
1
AN:
33478
American (AMR)
AF:
0.0000671
AC:
3
AN:
44720
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26130
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.000243
AC:
21
AN:
86256
European-Finnish (FIN)
AF:
0.0000187
AC:
1
AN:
53410
Middle Eastern (MID)
AF:
0.000520
AC:
3
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000216
AC:
24
AN:
1111992
Other (OTH)
AF:
0.0000331
AC:
2
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.500
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:
0.0000394
AC:
6
AN:
152290
Hom.:
0
Cov.:
32
AF XY:
0.0000269
AC XY:
2
AN XY:
74462
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41536
American (AMR)
AF:
0.00
AC:
0
AN:
15308
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3466
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5190
South Asian (SAS)
AF:
0.000415
AC:
2
AN:
4820
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10620
Middle Eastern (MID)
AF:
0.00340
AC:
1
AN:
294
European-Non Finnish (NFE)
AF:
0.0000441
AC:
3
AN:
68028
Other (OTH)
AF:
0.00
AC:
0
AN:
2116
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.485
Heterozygous variant carriers
0
1
1
2
2
3
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:
0.0000282
Hom.:
0
Bravo
AF:
0.0000227
ExAC
AF:
0.0000576
AC:
7
Asia WGS
AF:
0.000289
AC:
1
AN:
3478
EpiCase
AF:
0.000109
EpiControl
AF:
0.00

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:2Uncertain:2Benign:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Seizures-scoliosis-macrocephaly syndrome Pathogenic:2
Jul 07, 2018
Marseille Medical Genetics, U1251, Aix Marseille University, Inserm
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:research

- -

Nov 21, 2024
OMIM
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:literature only

- -

Exostoses, multiple, type 2 Uncertain:1Benign:1
Jan 13, 2018
Illumina Laboratory Services, Illumina
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as likely benign is not then subjected to further curation. The score for this variant resulted in a classification of likely benign for this disease. -

May 23, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces serine, which is neutral and polar, with leucine, which is neutral and non-polar, at codon 4 of the EXT2 protein (p.Ser4Leu). This variant is present in population databases (rs527624522, gnomAD 0.03%). This missense change has been observed in individual(s) with an autosomal recessive EXT2-related neurodevelopmental condition (PMID: 30075207). It has also been observed to segregate with disease in related individuals. Invitae’s hereditary multiple osteochondromas clinical variant model, which takes into account the clinical and family history, age, sex, and reported ancestry of multiple individuals with this EXT2 variant, predicts that it is benign with a negative predictive value of at least 95%. This is a validated machine learning model developed at Invitae that incorporates the clinical features of 50,122 individuals referred for testing at Invitae. ClinVar contains an entry for this variant (Variation ID: 304572). An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be tolerated. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Exostoses, multiple, type 2;C4225248:Seizures-scoliosis-macrocephaly syndrome Uncertain:1
Apr 08, 2024
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.15
BayesDel_addAF
Benign
-0.19
T
BayesDel_noAF
Benign
-0.21
CADD
Uncertain
25
DANN
Uncertain
0.98
DEOGEN2
Benign
0.28
T;T;.;.;.;T
Eigen
Benign
0.17
Eigen_PC
Uncertain
0.35
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.93
.;D;D;D;D;D
M_CAP
Benign
0.020
T
MetaRNN
Benign
0.17
T;T;T;T;T;T
MetaSVM
Benign
-0.92
T
MutationAssessor
Benign
0.97
L;.;.;L;.;L
PhyloP100
7.5
PrimateAI
Uncertain
0.65
T
PROVEAN
Benign
-0.47
N;D;N;N;N;N
REVEL
Benign
0.16
Sift
Uncertain
0.0050
D;D;D;D;D;D
Sift4G
Uncertain
0.029
D;D;D;D;D;D
Polyphen
0.15
B;.;.;P;.;B
Vest4
0.50
MutPred
0.39
Loss of disorder (P = 0);Loss of disorder (P = 0);Loss of disorder (P = 0);Loss of disorder (P = 0);.;Loss of disorder (P = 0);
MVP
0.77
MPC
0.27
ClinPred
0.11
T
GERP RS
5.3
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.15
gMVP
0.78
Mutation Taster
=1/99
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

Publications

Other links and lift over

dbSNP: rs527624522; hg19: chr11-44129273; COSMIC: COSV59152561; COSMIC: COSV59152561; API