NM_000520.6:c.1307_1308delTA

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong

The NM_000520.6(HEXA):​c.1307_1308delTA​(p.Ile436SerfsTer7) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000044 in 1,613,906 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Likely pathogenic (★★). Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000047 ( 0 hom. )

Consequence

HEXA
NM_000520.6 frameshift

Scores

Not classified

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:3

Conservation

PhyloP100: 0.174

Publications

0 publications found
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 Gene-Disease associations (from GenCC):
  • Tay-Sachs disease
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Myriad Women’s Health, Genomics England PanelApp, G2P, Labcorp Genetics (formerly Invitae), ClinGen

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 18 ACMG points.

PVS1
Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 15-72346548-CTA-C is Pathogenic according to our data. Variant chr15-72346548-CTA-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 189046.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
HEXANM_000520.6 linkc.1307_1308delTA p.Ile436SerfsTer7 frameshift_variant Exon 11 of 14 ENST00000268097.10 NP_000511.2 P06865-1A0A0S2Z3W3
HEXANM_001318825.2 linkc.1340_1341delTA p.Ile447SerfsTer7 frameshift_variant Exon 11 of 14 NP_001305754.1 P06865H3BP20B4DVA7
HEXANR_134869.3 linkn.1116-225_1116-224delTA intron_variant Intron 9 of 10

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
HEXAENST00000268097.10 linkc.1307_1308delTA p.Ile436SerfsTer7 frameshift_variant Exon 11 of 14 1 NM_000520.6 ENSP00000268097.6 P06865-1
ENSG00000260729ENST00000379915.4 linkn.413-225_413-224delTA intron_variant Intron 3 of 15 2 ENSP00000478716.1 A0A087WUJ7

Frequencies

GnomAD3 genomes
AF:
0.0000197
AC:
3
AN:
152168
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000483
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:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000796
AC:
2
AN:
251354
AF XY:
0.00
show subpopulations
Gnomad AFR exome
AF:
0.0000616
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.000163
GnomAD4 exome
AF:
0.0000465
AC:
68
AN:
1461738
Hom.:
0
AF XY:
0.0000330
AC XY:
24
AN XY:
727172
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26134
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39698
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86256
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53414
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5738
European-Non Finnish (NFE)
AF:
0.0000603
AC:
67
AN:
1111904
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60390
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.510
Heterozygous variant carriers
0
4
8
11
15
19
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
4
8
12
16
20
<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:
0.0000197
AC:
3
AN:
152168
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74330
show subpopulations
African (AFR)
AF:
0.0000483
AC:
2
AN:
41430
American (AMR)
AF:
0.00
AC:
0
AN:
15278
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5192
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4826
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10616
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68034
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.425
Heterozygous variant carriers
0
1
2
2
3
4
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.0000151
EpiCase
AF:
0.0000545
EpiControl
AF:
0.0000593

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Tay-Sachs disease Pathogenic:3
Nov 25, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change creates a premature translational stop signal (p.Ile436Serfs*7) in the HEXA gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in HEXA are known to be pathogenic (PMID: 1833974, 8490625). This variant is present in population databases (rs777042785, gnomAD 0.008%). This premature translational stop signal has been observed in individual(s) with Tay-Sachs disease (PMID: 22441121). ClinVar contains an entry for this variant (Variation ID: 189046). For these reasons, this variant has been classified as Pathogenic. -

Feb 16, 2021
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: HEXA c.1307_1308delTA (p.Ile436SerfsX7) 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 allele was found at a frequency of 8e-06 in 251354 control chromosomes (gnomAD). c.1307_1308delTA has been reported in the literature in an individual in homozygous state affected with Tay-Sachs Disease (Zampieri_2012). These data indicate that the variant may be associated with disease. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. No other clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014. Based on the evidence outlined above, the variant was classified as likely pathogenic. -

Nov 05, 2014
Counsyl
Significance:Likely pathogenic
Review Status:no assertion criteria provided
Collection Method:literature only

This submission and the accompanying classification are no longer maintained by the submitter. For more information on current observations and classification, please contact variantquestions@myriad.com. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
PhyloP100
0.17
Mutation Taster
=0/200
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: rs777042785; hg19: chr15-72638889; API