NM_000520.6:c.1528C>T

Variant names:

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PVS1_ModeratePM2PP5_Very_Strong

The NM_000520.6(HEXA):c.1528C>T(p.Arg510*) variant causes a stop gained, splice region change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000496 in 1,613,114 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Pathogenic (★★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)

Exomes 𝑓: 0.0000048 ( 0 hom. )

Consequence

HEXA
NM_000520.6 stop_gained, splice_region

Scores

Splicing: ADA: 0.03540

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:8

Conservation

PhyloP100: 3.44

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]

HEXA links:

ENSG00000260729 (HGNC:):

ENSG00000260729 links:

ENSG00000261460 (HGNC:58304):

ENSG00000261460 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 12 ACMG points.

PVS1

Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. Fraction of 0.039 CDS is truncated, and there are 0 pathogenic variants in the truncated region.

PM2

Very rare variant in population databases, with high coverage;

PP5

Variant 15-72344139-G-A is Pathogenic according to our data. Variant chr15-72344139-G-A is described in ClinVar as [Pathogenic]. Clinvar id is 188954.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
HEXA	NM_000520.6 link	c.1528C>T	p.Arg510*	stop_gained, splice_region_variant	Exon 14 of 14	ENST00000268097.10	NP_000511.2	P06865-1A0A0S2Z3W3
HEXA	NM_001318825.2 link	c.1561C>T	p.Arg521*	stop_gained, splice_region_variant	Exon 14 of 14		NP_001305754.1	P06865H3BP20B4DVA7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
HEXA	ENST00000268097.10 link	c.1528C>T	p.Arg510*	stop_gained, splice_region_variant	Exon 14 of 14	1	NM_000520.6	ENSP00000268097.6		P06865-1
ENSG00000260729	ENST00000379915.4 link	n.608+1307C>T		intron_variant	Intron 5 of 15	2		ENSP00000478716.1		A0A087WUJ7

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152142

Hom.:

Cov.:

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

AF:

0.00000479

AC:

AN:

1460972

Hom.:

Cov.:

AF XY:

0.00000550

AC XY:

AN XY:

726868

show subpopulations

Gnomad4 AFR exome

AF:

0.000120

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.0000116

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00000180

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.00000657

AC:

AN:

152142

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74334

show subpopulations

Gnomad4 AFR

AF:

0.0000241

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.00000756

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:8

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Tay-Sachs disease

Pathogenic:7

Jan 06, 2021

Baylor Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Nov 10, 2021

Myriad Genetics, Inc.

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

NM_000520.4(HEXA):c.1528C>T(R510*) is a nonsense variant classified as pathogenic in the context of hexosaminidase A deficiency. R510* has been observed in cases with relevant disease (PMID: 33547378, 27896118, 21567908). Functional assessments of this variant are not available in the literature. R510* has not been observed in population frequency databases. In summary, NM_000520.4(HEXA):c.1528C>T(R510*) is a nonsense variant in a gene where loss of function is a known mechanism of disease, is predicted to disrupt protein function, and has been observed more frequently in cases with the relevant disease than in healthy populations. Please note: this variant was assessed in the context of healthy population screening. -

Aug 26, 2010

Foundation for Research in Genetics and Endocrinology, FRIGE's Institute of Human Genetics

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: research

- -

Sep 28, 2021

Baylor Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was determined to be pathogenic according to ACMG Guidelines, 2015 [PMID:25741868]. -

Dec 09, 2017

Natera, Inc.

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

Apr 02, 2018

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Variant summary: HEXA c.1528C>T (p.Arg510X) results in a premature termination codon, predicted to cause a truncation of the encoded protein or absence of the protein due to nonsense mediated decay, which are commonly known mechanisms for disease. The variant was absent in 120496 control chromosomes (ExAC and publication controls). The variant, c.1528C>T, has been reported in the literature in multiple individuals affected with Tay-Sachs Disease. These data indicate that the variant is very likely to be associated with disease. At least one publication reports experimental evidence evaluating an impact on protein function. The most pronounced variant effect results in 10%-<30% of normal activity. A ClinVar submission from a clinical diagnostic laboratory (evaluation after 2014) cites the variant as "pathogenic." Based on the evidence outlined above, the variant was classified as pathogenic. -

Sep 06, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

For these reasons, this variant has been classified as Pathogenic. ClinVar contains an entry for this variant (Variation ID: 188954). This premature translational stop signal has been observed in individual(s) with hexosaminidase A deficiency (PMID: 21567908, 22789865, 27896118). This variant is not present in population databases (gnomAD no frequency). This sequence change creates a premature translational stop signal (p.Arg510*) in the HEXA gene. While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 20 amino acid(s) of the HEXA protein. -

not provided

Pathogenic:1

Jun 06, 2022

GeneDx

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Nonsense variant in the C-terminus predicted to result in protein truncation, as the last 20 amino acids are lost, and other loss-of-function variants have been reported downstream in HGMD.; Not observed at significant frequency in large population cohorts (gnomAD); This variant is associated with the following publications: (PMID: 27896118, 21567908, 22789865, 33547378) -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_addAF

Pathogenic

0.54

BayesDel_noAF

Pathogenic

0.54

CADD

Pathogenic

DANN

Uncertain

1.0

Eigen

Uncertain

0.68

Eigen_PC

Uncertain

0.53

FATHMM_MKL

Uncertain

0.96

Vest4

0.71

GERP RS

3.8

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Splicing

Name

Calibrated prediction

Score

Prediction

dbscSNV1_ADA

Benign

0.035

dbscSNV1_RF

Benign

0.42

SpliceAI score (max)

0.060

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.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over