15-72346679-C-T

Variant summary

Our verdict is Likely benign. Variant got -6 ACMG points: 0P and 6B. BP4_ModerateBS2

The NM_000520.6(HEXA):​c.1178G>A​(p.Arg393Gln) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000083 in 1,614,144 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 Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.00012 ( 0 hom., cov: 30)
Exomes 𝑓: 0.000079 ( 2 hom. )

Consequence

HEXA
NM_000520.6 missense

Scores

1
7
11

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:4

Conservation

PhyloP100: 2.52
Variant links:
Genes affected
HEXA (HGNC:4878): (hexosaminidase subunit alpha) This gene encodes a member of the glycosyl hydrolase 20 family of proteins. The encoded preproprotein is proteolytically processed to generate the alpha subunit of the lysosomal enzyme beta-hexosaminidase. This enzyme, together with the cofactor GM2 activator protein, catalyzes the degradation of the ganglioside GM2, and other molecules containing terminal N-acetyl hexosamines. Mutations in this gene lead to an accumulation of GM2 ganglioside in neurons, the underlying cause of neurodegenerative disorders termed the GM2 gangliosidoses, including Tay-Sachs disease (GM2-gangliosidosis type I). Alternative splicing results in multiple transcript variants, at least one of which encodes a preproprotein that is proteolytically processed. [provided by RefSeq, Jan 2016]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -6 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.13550046).
BS2
High Homozygotes in GnomAdExome4 at 2 AR gene

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
HEXANM_000520.6 linkc.1178G>A p.Arg393Gln missense_variant Exon 11 of 14 ENST00000268097.10 NP_000511.2 P06865-1A0A0S2Z3W3
HEXANM_001318825.2 linkc.1211G>A p.Arg404Gln missense_variant Exon 11 of 14 NP_001305754.1 P06865H3BP20B4DVA7
HEXANR_134869.3 linkn.1116-354G>A intron_variant Intron 9 of 10

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
HEXAENST00000268097.10 linkc.1178G>A p.Arg393Gln missense_variant Exon 11 of 14 1 NM_000520.6 ENSP00000268097.6 P06865-1
ENSG00000260729ENST00000379915.4 linkn.413-354G>A intron_variant Intron 3 of 15 2 ENSP00000478716.1 A0A087WUJ7

Frequencies

GnomAD3 genomes
AF:
0.000125
AC:
19
AN:
152196
Hom.:
0
Cov.:
30
show subpopulations
Gnomad AFR
AF:
0.000314
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.000414
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000588
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.000103
AC:
26
AN:
251478
Hom.:
0
AF XY:
0.000147
AC XY:
20
AN XY:
135916
show subpopulations
Gnomad AFR exome
AF:
0.000123
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.000719
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000176
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000787
AC:
115
AN:
1461830
Hom.:
2
Cov.:
33
AF XY:
0.000109
AC XY:
79
AN XY:
727212
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.000835
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000351
Gnomad4 OTH exome
AF:
0.0000662
GnomAD4 genome
AF:
0.000125
AC:
19
AN:
152314
Hom.:
0
Cov.:
30
AF XY:
0.000107
AC XY:
8
AN XY:
74480
show subpopulations
Gnomad4 AFR
AF:
0.000313
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.000414
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000588
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.000115
Hom.:
0
Bravo
AF:
0.000125
ESP6500AA
AF:
0.000227
AC:
1
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.000107
AC:
13

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:4
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Tay-Sachs disease Uncertain:3
Sep 01, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This sequence change replaces arginine, which is basic and polar, with glutamine, which is neutral and polar, at codon 393 of the HEXA protein (p.Arg393Gln). This variant is present in population databases (rs370266293, gnomAD 0.07%). This variant has not been reported in the literature in individuals affected with HEXA-related conditions. ClinVar contains an entry for this variant (Variation ID: 554870). Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest 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. -

Sep 16, 2020
Natera, Inc.
Significance: Uncertain significance
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

Nov 16, 2017
Counsyl
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

not specified Uncertain:1
Aug 09, 2018
ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The HEXA c.1178G>A; p.Arg393Gln variant (rs370266293), to our knowledge, is not reported in the medical literature or gene specific databases; however, another variant at this codon (c.1178G>C; p.R393P) has been reported in the homozygous state in an individual with Tay-Sachs disease (Mistri 2012). This variant is found in the South Asian population with an overall allele frequency of 0.07% (21/30780 alleles) in the Genome Aggregation Database. The arginine at codon 393 is moderately conserved, and computational analyses (SIFT: damaging, PolyPhen-2: benign) predict conflicting effects of the p.Arg393Gln variant on protein structure/function. Due to limited information, the clinical significance of the p.Arg393Gln variant is uncertain at this time. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.099
BayesDel_addAF
Benign
-0.11
T
BayesDel_noAF
Uncertain
-0.030
CADD
Uncertain
24
DANN
Pathogenic
1.0
DEOGEN2
Uncertain
0.76
D;.;D
Eigen
Benign
0.015
Eigen_PC
Benign
0.041
FATHMM_MKL
Benign
0.71
D
LIST_S2
Benign
0.79
T;T;T
M_CAP
Uncertain
0.17
D
MetaRNN
Benign
0.14
T;T;T
MetaSVM
Uncertain
0.33
D
MutationAssessor
Benign
1.8
L;.;.
PrimateAI
Benign
0.31
T
PROVEAN
Benign
-0.99
N;N;N
REVEL
Uncertain
0.41
Sift
Uncertain
0.016
D;D;D
Sift4G
Uncertain
0.048
D;D;D
Polyphen
0.85
P;.;.
Vest4
0.20
MVP
0.95
MPC
0.26
ClinPred
0.089
T
GERP RS
3.8
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.30
gMVP
0.73

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: rs370266293; hg19: chr15-72639020; API