NM_000434.4:c.727G>A

Variant names:

• chr6-31860510-C-T
• rs104893983
• NM_000434.4:c.727G>A

Variant summary

Our verdict is Pathogenic. The variant received 15 ACMG points: 15P and 0B. PM2 PP2 PP3_Strong PP5_Very_Strong

The NM_000434.4(NEU1):​c.727G>A​(p.Gly243Arg) variant causes a missense change. The variant allele was found at a frequency of 0.000015 in 1,461,872 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 Likely pathogenic (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.000015 (0 hom.)
• Consequence: NEU1 NM_000434.4 missense
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:4
• Conservation: PhyloP100: 7.18
• Publications: 18 publications found

Genes affected

NEU1 (HGNC:7758): (neuraminidase 1) The protein encoded by this gene is a lysosomal enzyme that cleaves terminal sialic acid residues from substrates such as glycoproteins and glycolipids. In the lysosome, this enzyme is part of a heterotrimeric complex together with beta-galactosidase and cathepsin A (the latter is also referred to as 'protective protein'). Mutations in this gene can lead to sialidosis, a lysosomal storage disease that can be type 1 (cherry red spot-myoclonus syndrome or normosomatic type), which is late-onset, or type 2 (the dysmorphic type), which occurs at an earlier age with increased severity. [provided by RefSeq, Jul 2008]

NEU1 Gene-Disease associations (from GenCC):

• sialidosis

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
• sialidosis type 2

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: G2P, Genomics England PanelApp, Labcorp Genetics (formerly Invitae)
• congenital sialidosis type 2

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• juvenile sialidosis type 2

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• sialidosis type 1

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 15 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 24 curated pathogenic missense variants (we use a threshold of 10). The gene has 5 curated benign missense variants. Gene score misZ: 1.4218 (below the threshold of 3.09). Trascript score misZ: 2.2638 (below the threshold of 3.09). GenCC associations: The gene is linked to sialidosis, sialidosis type 2, congenital sialidosis type 2, sialidosis type 1, juvenile sialidosis type 2.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.984
• PP5: Variant 6-31860510-C-T is Pathogenic according to our data. Variant chr6-31860510-C-T is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 2450.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
NEU1	NM_000434.4	c.727G>A	p.Gly243Arg	missense_variant	Exon 4 of 6	ENST00000375631.5	NP_000425.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
NEU1	ENST00000375631.5	c.727G>A	p.Gly243Arg	missense_variant	Exon 4 of 6	1	NM_000434.4	ENSP00000364782.4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000795 AC: 2 AN: 251446 AF XY: 0.00

Gnomad AFR exome AF: 0.0000615

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.0000544

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000150 AC: 22 AN: 1461872 Hom.: 0 Cov.: 31 AF XY: 0.0000193 AC XY: 14 AN XY: 727236

African (AFR) AF: 0.0000299 AC: 1 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: 0.0000504 AC: 2 AN: 39700

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

European-Finnish (FIN) AF: 0.0000187 AC: 1 AN: 53400

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

European-Non Finnish (NFE) AF: 0.0000162 AC: 18 AN: 1112010

Other (OTH) AF: 0.00 AC: 0 AN: 60396

GnomAD4 genome Cov.: 32

Alfa AF: 0.00000965 Hom.: 0

ESP6500AA AF: 0.00 AC: 0

ESP6500EA AF: 0.000116 AC: 1

ExAC AF: 0.0000165 AC: 2

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Pathogenic:3

Dec 23, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces glycine, which is neutral and non-polar, with arginine, which is basic and polar, at codon 243 of the NEU1 protein (p.Gly243Arg). This variant is present in population databases (rs104893983, gnomAD 0.007%). This missense change has been observed in individual(s) with sialidosis type I (PMID: 10944856, 19415310). ClinVar contains an entry for this variant (Variation ID: 2450). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is not expected to disrupt NEU1 protein function with a negative predictive value of 80%. Experimental studies have shown that this missense change affects NEU1 function (PMID: 10944856). In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. -

Jun 28, 2013

Eurofins Ntd Llc (ga)

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Sep 20, 2023

GeneDx

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Published functional studies found this variant is associated with significantly reduced enzyme activity and mislocalization (Naganawa Y et al., 2000); Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 34426522, 16538002, 10944856, 11829139, 34992946, 32472645, 19415310) -

Sialidosis type 1 Pathogenic:1

Jan 01, 2000

OMIM

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: literature only

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.58
BayesDel_addAF	Pathogenic	0.32	D
BayesDel_noAF	Pathogenic	0.40
CADD	Pathogenic	26
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.97	D
Eigen	Uncertain	0.63
Eigen_PC	Uncertain	0.48
FATHMM_MKL	Uncertain	0.96	D
M_CAP	Uncertain	0.22	D
MetaRNN	Pathogenic	0.98	D
MetaSVM	Uncertain	0.78	D
MutationAssessor	Pathogenic	3.1	M
PhyloP100		7.2
PrimateAI	Uncertain	0.60	T
PROVEAN	Pathogenic	-6.1	D
REVEL	Pathogenic	0.79
Sift	Uncertain	0.0010	D
Sift4G	Uncertain	0.056	T
Polyphen		0.98	D
Vest4		0.99
MutPred		0.94		Loss of glycosylation at S244 (P = 0.0532);
MVP		0.99
MPC		1.5
ClinPred		0.99	D
GERP RS		5.3
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
Varity_R		0.58
gMVP		0.94
Mutation Taster		=12/88	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs104893983; hg19: chr6-31828287; COSMIC: COSV57669272; COSMIC: COSV57669272;