chr8-117799797-T-A

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2PP3_Moderate

The NM_000127.3(EXT1):​c.2156A>T​(p.His719Leu) variant causes a missense change. The variant allele was found at a frequency of 0.000000684 in 1,461,890 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 Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. H719P) has been classified as Uncertain significance.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

EXT1
NM_000127.3 missense

Scores

5
9
5

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 5.14
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 4 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.858

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE UniProt
EXT1NM_000127.3 linkuse as main transcriptc.2156A>T p.His719Leu missense_variant 11/11 ENST00000378204.7

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Appris UniProt
EXT1ENST00000378204.7 linkuse as main transcriptc.2156A>T p.His719Leu missense_variant 11/111 NM_000127.3 P1
EXT1ENST00000684189.1 linkuse as main transcriptn.1623A>T non_coding_transcript_exon_variant 11/11
EXT1ENST00000684443.1 linkuse as main transcriptn.2282A>T non_coding_transcript_exon_variant 2/2
EXT1ENST00000437196.1 linkuse as main transcript downstream_gene_variant 5

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD3 exomes
AF:
0.00000398
AC:
1
AN:
251294
Hom.:
0
AF XY:
0.00
AC XY:
0
AN XY:
135808
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 SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
6.84e-7
AC:
1
AN:
1461890
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
727246
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.0000252
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
Cov.:
32
ExAC
AF:
0.00000824
AC:
1

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Inborn genetic diseases Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingAmbry GeneticsAug 08, 2023The c.2156A>T (p.H719L) alteration is located in exon 11 (coding exon 11) of the EXT1 gene. This alteration results from a A to T substitution at nucleotide position 2156, causing the histidine (H) at amino acid position 719 to be replaced by a leucine (L). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.55
BayesDel_addAF
Pathogenic
0.26
D
BayesDel_noAF
Pathogenic
0.30
CADD
Pathogenic
29
DANN
Benign
0.97
DEOGEN2
Pathogenic
0.82
D
Eigen
Uncertain
0.51
Eigen_PC
Uncertain
0.55
FATHMM_MKL
Uncertain
0.97
D
LIST_S2
Uncertain
0.90
D
M_CAP
Benign
0.084
D
MetaRNN
Pathogenic
0.86
D
MetaSVM
Uncertain
0.11
D
MutationAssessor
Uncertain
2.6
M
MutationTaster
Benign
1.0
D
PrimateAI
Uncertain
0.75
T
PROVEAN
Uncertain
-4.1
D
REVEL
Pathogenic
0.76
Sift
Benign
0.066
T
Sift4G
Benign
0.19
T
Polyphen
0.89
P
Vest4
0.76
MutPred
0.76
Loss of catalytic residue at Q721 (P = 0.2589);
MVP
0.89
MPC
2.2
ClinPred
0.90
D
GERP RS
6.0
Varity_R
0.57
gMVP
0.84

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

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs751787859; hg19: chr8-118812036; API