rs794727505

Positions:

• chr9-36246181-A-G

Variant summary

Our verdict is Likely pathogenic. Variant got 7 ACMG points: 7P and 0B. PM1 PP2 PP3_Strong

The NM_001128227.3(GNE):​c.559T>C​(p.Tyr187His) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000616 in 1,461,868 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 Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. Y187C) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000062 (0 hom.)
• Consequence: GNE NM_001128227.3 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1 U:3
• Conservation: PhyloP100: 8.44

Genes affected

GNE (HGNC:23657): (glucosamine (UDP-N-acetyl)-2-epimerase/N-acetylmannosamine kinase) The protein encoded by this gene is a bifunctional enzyme that initiates and regulates the biosynthesis of N-acetylneuraminic acid (NeuAc), a precursor of sialic acids. It is a rate-limiting enzyme in the sialic acid biosynthetic pathway. Sialic acid modification of cell surface molecules is crucial for their function in many biologic processes, including cell adhesion and signal transduction. Differential sialylation of cell surface molecules is also implicated in the tumorigenicity and metastatic behavior of malignant cells. Mutations in this gene are associated with sialuria, autosomal recessive inclusion body myopathy, and Nonaka myopathy. Alternative splicing of this gene results in transcript variants encoding different isoforms. [provided by RefSeq, Jul 2008]

CLTA (HGNC:2090): (clathrin light chain A) Clathrin is a large, soluble protein composed of heavy and light chains. It functions as the main structural component of the lattice-type cytoplasmic face of coated pits and vesicles which entrap specific macromolecules during receptor-mediated endocytosis. This gene encodes one of two clathrin light chain proteins which are believed to function as regulatory elements. Alternative splicing results in multiple transcript variants. Related pseudogenes have been identified on chromosomes 8 and 12. [provided by RefSeq, May 2010]

ACMG classification

Verdict is Likely_pathogenic. Variant got 7 ACMG points.

• PM1: In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 8 uncertain in NM_001128227.3
• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), GNE. . Gene score misZ 2.5904 (greater than the threshold 3.09). Trascript score misZ 4.032 (greater than threshold 3.09). GenCC has associacion of gene with macrothrombocytopenia, isolated, platelet-type bleeding disorder 19, sialuria, GNE myopathy.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.941

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
GNE	NM_001128227.3	c.559T>C	p.Tyr187His	missense_variant	3/12	ENST00000396594.8
GNE	NM_005476.7	c.466T>C	p.Tyr156His	missense_variant	3/12	ENST00000642385.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
GNE	ENST00000396594.8	c.559T>C	p.Tyr187His	missense_variant	3/12	1	NM_001128227.3
GNE	ENST00000642385.2	c.466T>C	p.Tyr156His	missense_variant	3/12		NM_005476.7	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000796 AC: 2 AN: 251394 Hom.: 0 AF XY: 0.0000147 AC XY: 2 AN XY: 135862

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.0000653

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000616 AC: 9 AN: 1461868 Hom.: 0 Cov.: 33 AF XY: 0.00000688 AC XY: 5 AN XY: 727238

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.000104

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:1 Uncertain:3

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Thrombocytopenia Pathogenic:1

Likely pathogenic, criteria provided, single submitter

research

NIHR Bioresource Rare Diseases, University of Cambridge

Feb 01, 2019

- -

Sialuria;C1853926:GNE myopathy Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Feb 03, 2022

This sequence change replaces tyrosine, which is neutral and polar, with histidine, which is basic and polar, at codon 187 of the GNE protein (p.Tyr187His). This variant is present in population databases (rs794727505, gnomAD 0.006%). This missense change has been observed in individual(s) with clinical features of myopathy (PMID: 24796702, 28320138; Invitae). ClinVar contains an entry for this variant (Variation ID: 196410). Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be disruptive. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

GNE myopathy Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Counsyl

May 19, 2017

- -

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Eurofins Ntd Llc (ga)

Jun 23, 2014

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.80
BayesDel_addAF	Pathogenic	0.31	D
BayesDel_noAF	Pathogenic	0.39
CADD	Pathogenic	28
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.95	D;.;D;.;.;.;D
Eigen	Pathogenic	0.74
Eigen_PC	Pathogenic	0.75
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.98	.;D;D;D;D;D;.
M_CAP	Pathogenic	0.92	D
MetaRNN	Pathogenic	0.94	D;D;D;D;D;D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Benign	1.8	L;.;L;.;.;L;L
MutationTaster	Benign	1.0	D;D;D;D;D;D
PrimateAI	Pathogenic	0.91	D
PROVEAN	Uncertain	-2.7	.;D;D;.;N;D;D
REVEL	Pathogenic	0.95
Sift	Uncertain	0.0010	.;D;D;.;D;D;D
Sift4G	Uncertain	0.053	.;T;D;D;T;D;D
Polyphen		1.0	D;D;D;.;.;.;D
Vest4		0.88, 0.90, 0.86, 0.84, 0.86
MutPred		0.77		Loss of stability (P = 0.0884);.;Loss of stability (P = 0.0884);.;.;Loss of stability (P = 0.0884);Loss of stability (P = 0.0884);
MVP		0.98
MPC		1.6
ClinPred		0.89	D
GERP RS		5.8
Varity_R		0.92
gMVP		0.83

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

LitVar

Other links and lift over

dbSNP: rs794727505; hg19: chr9-36246178;