rs878854424

Variant names:

• chr2-196220113-T-C
• rs878854424
• NM_001348768.2:c.4334A>G

Variant summary

Our verdict is Likely pathogenic. Variant got 9 ACMG points: 9P and 0B. PM2 PM5 PP2 PP3_Strong

The NM_001348768.2(HECW2):​c.4334A>G​(p.Glu1445Gly) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 12/21 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. E1445Q) has been classified as Pathogenic.

• Frequency: Genomes: not found (cov: 32)
• Consequence: HECW2 NM_001348768.2 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter P:1 U:1 O:1
• Conservation: PhyloP100: 7.67

Genes affected

HECW2 (HGNC:29853): (HECT, C2 and WW domain containing E3 ubiquitin protein ligase 2) This gene encodes a member of a family of E3 ubiquitin ligases which plays an important role in the proliferation, migration and differentiation of neural crest cells as a regulator of glial cell line-derived neurotrophic factor (GDNF)/Ret signaling. This gene also plays an important role in angiogenesis through stabilization of endothelial cell-to-cell junctions as a regulator of angiomotin-like 1 stability. The encoded protein contains an N-terminal calcium/lipid-binding (C2) domain involved in membrane targeting, two-four WW domains responsible for cellular localization and substrate recognition, and a C-terminal homologous with E6-associated protein C-terminus (HECT) catalytic domain. Naturally occurring mutations in this gene are associated with neurodevelopmental delay, hypotonia, and epilepsy. The decreased expression of this gene in the aganglionic colon is associated with Hirschsprung's disease. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Feb 2017]

ACMG classification

Verdict is Likely_pathogenic. Variant got 9 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr2-196220114-C-G is described in Lovd as [Pathogenic].
• PP2: Missense variant in the HECW2 gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 31 curated pathogenic missense variants (we use a threshold of 10). The gene has 62 curated benign missense variants. Gene score misZ: 3.3052 (above the threshold of 3.09). Trascript score misZ: 3.6429 (above the threshold of 3.09). GenCC associations: The gene is linked to neurodevelopmental disorder with hypotonia, seizures, and absent language, complex neurodevelopmental disorder.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.964

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
HECW2	NM_001348768.2	c.4334A>G	p.Glu1445Gly	missense_variant	Exon 26 of 29	ENST00000644978.2	NP_001335697.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
HECW2	ENST00000644978.2	c.4334A>G	p.Glu1445Gly	missense_variant	Exon 26 of 29		NM_001348768.2	ENSP00000495418.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Pathogenic:1 Uncertain:1 Other:1

Revision: criteria provided, single submitter

Submissions by phenotype

Neurodevelopmental disorder with hypotonia, seizures, and absent language Pathogenic:1 Uncertain:1

Jan 10, 2018

OMIM

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: literature only

- -

Mar 07, 2018

Undiagnosed Diseases Network, NIH

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

not provided Other:1

-

GenomeConnect, ClinGen

Significance: not provided

Review Status: no classification provided

Collection Method: phenotyping only

GenomeConnect assertions are reported exactly as they appear on the patient-provided report from the testing laboratory. GenomeConnect staff make no attempt to reinterpret the clinical significance of the variant. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.40	D
BayesDel_noAF	Pathogenic	0.34
CADD	Pathogenic	28
DANN	Pathogenic	1.0
DEOGEN2	Benign	0.38	T;.;T;T
Eigen	Pathogenic	0.94
Eigen_PC	Pathogenic	0.84
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Pathogenic	0.99	.;D;.;D
M_CAP	Uncertain	0.26	D
MetaRNN	Pathogenic	0.96	D;D;D;D
MetaSVM	Uncertain	0.51	D
MutationAssessor	Pathogenic	4.3	H;.;H;H
PrimateAI	Pathogenic	0.87	D
PROVEAN	Pathogenic	-6.6	D;.;.;.
REVEL	Pathogenic	0.88
Sift	Pathogenic	0.0	D;.;.;.
Sift4G	Pathogenic	0.0010	D;.;.;.
Polyphen		1.0	D;.;D;D
Vest4		0.99
MutPred		0.89		Loss of stability (P = 0.0813);.;Loss of stability (P = 0.0813);Loss of stability (P = 0.0813);
MVP		0.94
MPC		2.3
ClinPred		1.0	D
GERP RS		5.1
Varity_R		0.94
gMVP		0.96

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: rs878854424; hg19: chr2-197084837;