rs786204515

Variant names:

• chr15-72349117-A-AT
• rs786204515
• NM_000520.6:c.947dupA

Variant summary

Our verdict is Pathogenic. The variant received 11 ACMG points: 11P and 0B. PVS1 PM2 PP5

The NM_000520.6(HEXA):​c.947dupA​(p.Tyr316fs) variant causes a frameshift, stop gained change. The variant allele was found at a frequency of 0.00000137 in 1,461,812 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Likely pathogenic (no stars). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: HEXA NM_000520.6 frameshift, stop_gained
• Clinical Significance: Likely pathogenic no assertion criteria provided P:1
• Conservation: PhyloP100: 5.12
• Publications: 0 publications found

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: ClinGen, Myriad Women’s Health, Labcorp Genetics (formerly Invitae), Genomics England PanelApp, G2P

ENSG00000260729 (HGNC:):

CELF6-AS1 (HGNC:58304):

ACMG classification

Our verdict: Pathogenic. The variant received 11 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 15-72349117-A-AT is Pathogenic according to our data. Variant chr15-72349117-A-AT is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 188855.Status of the report is no_assertion_criteria_provided, 0 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000520.6. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	HEXA	NM_000520.6	MANE Select	c.947dupA	p.Tyr316fs	frameshift stop_gained	Exon 8 of 14	NP_000511.2	P06865-1
	HEXA	NM_001318825.2		c.980dupA	p.Tyr327fs	frameshift stop_gained	Exon 8 of 14	NP_001305754.1	H3BP20
	HEXA	NR_134869.3		n.989dupA		non_coding_transcript_exon	Exon 8 of 11

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	HEXA	ENST00000268097.10	TSL:1 MANE Select	c.947dupA	p.Tyr316fs	frameshift stop_gained	Exon 8 of 14	ENSP00000268097.6	P06865-1
	HEXA	ENST00000567159.5	TSL:1	c.947dupA	p.Tyr316fs	frameshift stop_gained	Exon 8 of 13	ENSP00000456489.1	H3BS10
	ENSG00000260729	ENST00000379915.4	TSL:2	n.413-2793dupA		intron	N/A	ENSP00000478716.1	A0A087WUJ7

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461812 Hom.: 0 Cov.: 32 AF XY: 0.00000275 AC XY: 2 AN XY: 727210

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: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53408

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00000180 AC: 2 AN: 1111944

Other (OTH) AF: 0.00 AC: 0 AN: 60394

GnomAD4 genome Cov.: 32

ClinVar

ClinVar submissions

Significance: Likely pathogenic

Revision: no assertion criteria provided

Pathogenic	VUS	Benign	Condition
1	-	-	Tay-Sachs disease (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
PhyloP100		5.1
Mutation Taster		=0/200	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.080		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs786204515; hg19: chr15-72641458;