rs28940871

Variant names:

• chr15-72346305-G-C
• rs28940871
• NM_000520.6:c.1351C>G

Variant summary

Our verdict is Likely pathogenic. The variant received 8 ACMG points: 8P and 0B. PM1 PM2 PP3_Strong

The NM_000520.6(HEXA):​c.1351C>G​(p.Leu451Val) variant causes a missense change. The variant allele was found at a frequency of 0.00000124 in 1,613,802 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance,Affects (no stars).

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: HEXA NM_000520.6 missense
• Clinical Significance: Uncertain significance; Affects no assertion criteria provided U:1 O:1
• Conservation: PhyloP100: 5.79
• Publications: 6 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: Likely_pathogenic. The variant received 8 ACMG points.

• PM1: In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 15 uncertain in NM_000520.6
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.953

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.1351C>G	p.Leu451Val	missense	Exon 12 of 14	NP_000511.2	P06865-1
	HEXA	NM_001318825.2		c.1384C>G	p.Leu462Val	missense	Exon 12 of 14	NP_001305754.1	H3BP20
	HEXA	NR_134869.3		n.1136C>G		non_coding_transcript_exon	Exon 10 of 11

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	HEXA	ENST00000268097.10	TSL:1 MANE Select	c.1351C>G	p.Leu451Val	missense	Exon 12 of 14	ENSP00000268097.6	P06865-1
	HEXA	ENST00000567159.5	TSL:1	c.1351C>G	p.Leu451Val	missense	Exon 12 of 13	ENSP00000456489.1	H3BS10
	ENSG00000260729	ENST00000379915.4	TSL:2	n.433C>G		non_coding_transcript_exon	Exon 4 of 16	ENSP00000478716.1	A0A087WUJ7

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152116 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.000192

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: 6.84e-7 AC: 1 AN: 1461686 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 727154

African (AFR) AF: 0.00 AC: 0 AN: 33472

American (AMR) AF: 0.00 AC: 0 AN: 44708

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26122

East Asian (EAS) AF: 0.0000252 AC: 1 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86234

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53418

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5766

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111876

Other (OTH) AF: 0.00 AC: 0 AN: 60390

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152116 Hom.: 0 Cov.: 32 AF XY: 0.0000135 AC XY: 1 AN XY: 74320

African (AFR) AF: 0.00 AC: 0 AN: 41384

American (AMR) AF: 0.00 AC: 0 AN: 15276

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3472

East Asian (EAS) AF: 0.000192 AC: 1 AN: 5196

South Asian (SAS) AF: 0.00 AC: 0 AN: 4830

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10606

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 68038

Other (OTH) AF: 0.00 AC: 0 AN: 2086

Alfa AF: 0.00 Hom.: 0

ClinVar

ClinVar submissions

Significance: Uncertain significance; Affects

Revision: no assertion criteria provided

Pathogenic	VUS	Benign	Condition
-	1	-	Tay-Sachs disease (2)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.22
BayesDel_addAF	Pathogenic	0.49	D
BayesDel_noAF	Pathogenic	0.47
CADD	Uncertain	24
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.95	D
Eigen	Pathogenic	0.73
Eigen_PC	Uncertain	0.63
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.94	D
M_CAP	Uncertain	0.13	D
MetaRNN	Pathogenic	0.95	D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	3.7	H
PhyloP100		5.8
PrimateAI	Uncertain	0.60	T
PROVEAN	Uncertain	-2.7	D
REVEL	Pathogenic	0.83
Sift	Uncertain	0.0020	D
Sift4G	Uncertain	0.0040	D
Polyphen		0.99	D
Vest4		0.82
MutPred		0.87		Loss of stability (P = 0.0481)
MVP		0.99
MPC		0.59
ClinPred		0.98	D
GERP RS		4.9
RBP_binding_hub_radar		0.92
RBP_regulation_power_radar		2.0
Varity_R		0.87
gMVP		0.90
Mutation Taster		=2/98	disease causing

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

Other links and lift over

dbSNP: rs28940871; hg19: chr15-72638646;