Genetic Variant HEXB:p.Pro11Pro (chr5-74685293-G-C) – ACMG Classification: Likely_benign (-3 pts)

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 2P and 5B. PM2BP4_StrongBP7

The NM_000521.4(HEXB):c.33G>C(p.Pro11Pro) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000714 in 1,401,322 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Synonymous variant affecting the same amino acid position (i.e. P11P) has been classified as Likely benign.

Frequency

Genomes: not found (cov: 31)

Exomes 𝑓: 7.1e-7 ( 0 hom. )

Consequence

HEXB
NM_000521.4 synonymous

Scores

Clinical Significance

Not reported in ClinVar

Conservation

PhyloP100: -0.246

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

HEXB links:

ENSG00000306131 (HGNC:):

ENSG00000306131 links:

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -3 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (BayesDel_noAF=-0.72).

BP7

Synonymous conserved (PhyloP=-0.246 with no splicing effect.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000521.4. 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
	HEXB	NM_000521.4	MANE Select	c.33G>C	p.Pro11Pro	synonymous	Exon 1 of 14	NP_000512.2	P07686
	HEXB	NM_001292004.2		c.-376-4035G>C		intron	N/A	NP_001278933.1	Q5URX0

Ensembl Transcripts

Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
HEXB	ENST00000261416.12	TSL:1 MANE Select	c.33G>C	p.Pro11Pro	synonymous	Exon 1 of 14	ENSP00000261416.7	P07686
HEXB	ENST00000511181.5	TSL:1	c.-376-4035G>C		intron	N/A	ENSP00000426285.1	Q5URX0
HEXB	ENST00000513079.5	TSL:2	n.98G>C		non_coding_transcript_exon	Exon 1 of 6

Frequencies

GnomAD3 genomes

Cov.:

GnomAD4 exome

AF:

7.14e-7

AC:

AN:

1401322

Hom.:

Cov.:

AF XY:

0.00000144

AC XY:

AN XY:

692966

show subpopulations

African (AFR)

AF:

0.0000316

AC:

AN:

31604

American (AMR)

AF:

0.00

AC:

AN:

37618

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

25134

East Asian (EAS)

AF:

0.00

AC:

AN:

36446

South Asian (SAS)

AF:

0.00

AC:

AN:

80468

European-Finnish (FIN)

AF:

0.00

AC:

AN:

41012

Middle Eastern (MID)

AF:

0.00

AC:

AN:

4768

European-Non Finnish (NFE)

AF:

0.00

AC:

AN:

1086104

Other (OTH)

AF:

0.00

AC:

AN:

58168

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.575

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Exome Het

Variant carriers

<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

Cov.:

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name

Calibrated prediction

Score

Prediction

BayesDel_noAF

Benign

-0.72

CADD

Benign

6.7

(source)

DANN

Benign

0.61

PhyloP100

-0.25

PromoterAI

0.038

Neutral

(source)

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

You must be logged in to view publications. This limit was set because tens of millions (!) of queries from AI bots are generated daily.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

Publications

ACMG classification

Variant Effect in Transcripts

RefSeq Transcripts

Ensembl Transcripts

Frequencies

Age Distribution

ClinVar

Computational scores

Splicing

Publications

Other links and lift over