5-74685292-C-T

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2BP4_Strong

The NM_000521.4(HEXB):​c.32C>T​(p.Pro11Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000657 in 152,164 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/20 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Synonymous variant affecting the same amino acid position (i.e. P11P) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 31)
Exomes 𝑓: 0.0 ( 0 hom. )
Failed GnomAD Quality Control

Consequence

HEXB
NM_000521.4 missense

Scores

3
13

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: -2.11

Publications

0 publications found
Variant links:
Genes affected
HEXB (HGNC:4879): (hexosaminidase subunit beta) Hexosaminidase B is the beta subunit of the lysosomal enzyme beta-hexosaminidase that, together with the cofactor GM2 activator protein, catalyzes the degradation of the ganglioside GM2, and other molecules containing terminal N-acetyl hexosamines. Beta-hexosaminidase is composed of two subunits, alpha and beta, which are encoded by separate genes. Both beta-hexosaminidase alpha and beta subunits are members of family 20 of glycosyl hydrolases. Mutations in the alpha or beta subunit genes lead to an accumulation of GM2 ganglioside in neurons and neurodegenerative disorders termed the GM2 gangliosidoses. Beta subunit gene mutations lead to Sandhoff disease (GM2-gangliosidosis type II). Alternatively spliced transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, May 2014]
HEXB Gene-Disease associations (from GenCC):
  • Sandhoff disease
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics, G2P, ClinGen, Genomics England PanelApp, Myriad Women’s Health

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -2 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.04984188).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
HEXBNM_000521.4 linkc.32C>T p.Pro11Leu missense_variant Exon 1 of 14 ENST00000261416.12 NP_000512.2 P07686A0A024RAJ6
HEXBNM_001292004.2 linkc.-376-4036C>T intron_variant Intron 1 of 13 NP_001278933.1 P07686Q5URX0

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
HEXBENST00000261416.12 linkc.32C>T p.Pro11Leu missense_variant Exon 1 of 14 1 NM_000521.4 ENSP00000261416.7 P07686

Frequencies

GnomAD3 genomes
AF:
0.00000658
AC:
1
AN:
152050
Hom.:
0
Cov.:
31
show subpopulations
Gnomad AFR
AF:
0.0000241
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:
0.00
Gnomad OTH
AF:
0.00
GnomAD4 exome
Data not reliable, filtered out with message: AC0
AF:
0.00
AC:
0
AN:
1400704
Hom.:
0
Cov.:
31
AF XY:
0.00
AC XY:
0
AN XY:
692586
African (AFR)
AF:
0.00
AC:
0
AN:
31588
American (AMR)
AF:
0.00
AC:
0
AN:
37566
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25132
East Asian (EAS)
AF:
0.00
AC:
0
AN:
36402
South Asian (SAS)
AF:
0.00
AC:
0
AN:
80408
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
40834
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
4734
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1085882
Other (OTH)
AF:
0.00
AC:
0
AN:
58158
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152164
Hom.:
0
Cov.:
31
AF XY:
0.0000134
AC XY:
1
AN XY:
74382
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41532
American (AMR)
AF:
0.00
AC:
0
AN:
15296
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5122
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4814
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10616
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
290
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
67994
Other (OTH)
AF:
0.00
AC:
0
AN:
2116
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.725
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

ClinVar

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

Submissions by phenotype

Sandhoff disease Uncertain:1
Oct 16, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces proline, which is neutral and non-polar, with leucine, which is neutral and non-polar, at codon 11 of the HEXB protein (p.Pro11Leu). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with HEXB-related conditions. ClinVar contains an entry for this variant (Variation ID: 1982906). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is not expected to disrupt HEXB protein function with a negative predictive value of 95%. 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. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.12
BayesDel_addAF
Benign
-0.065
T
BayesDel_noAF
Benign
-0.33
CADD
Benign
0.28
DANN
Benign
0.86
Eigen
Benign
-2.1
Eigen_PC
Benign
-2.2
FATHMM_MKL
Benign
0.0030
N
M_CAP
Uncertain
0.10
D
MetaRNN
Benign
0.050
T
MetaSVM
Uncertain
-0.12
T
PhyloP100
-2.1
PrimateAI
Uncertain
0.51
T
PROVEAN
Benign
0.25
N
REVEL
Benign
0.22
Sift
Benign
0.38
T
Sift4G
Benign
0.98
T
Vest4
0.060
MutPred
0.38
Loss of glycosylation at P11 (P = 0.0135);
MVP
0.45
MPC
0.18
ClinPred
0.13
T
GERP RS
-8.9
PromoterAI
-0.042
Neutral
RBP_binding_hub_radar
0.92
RBP_regulation_power_radar
3.1
gMVP
0.36
Mutation Taster
=96/4
polymorphism

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: rs1454404113; hg19: chr5-73981117; API