4-5640789-G-C

Variant names:

• chr4-5640789-G-C
• rs137852924
• NM_147127.5:c.1195C>G

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PM2 PP3

The NM_147127.5(EVC2):​c.1195C>G​(p.Arg399Gly) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,882 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 (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R399Q) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: EVC2 NM_147127.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 3.47
• Publications: 13 publications found

Genes affected

EVC2 (HGNC:19747): (EvC ciliary complex subunit 2) This gene encodes a protein that functions in bone formation and skeletal development. Mutations in this gene, as well as in a neighboring gene that lies in a head-to-head configuration, cause Ellis-van Creveld syndrome, an autosomal recessive skeletal dysplasia that is also known as chondroectodermal dysplasia. Mutations in this gene also cause acrofacial dysostosis Weyers type, also referred to as Curry-Hall syndrome, a disease that combines limb and facial abnormalities. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Oct 2009]

EVC2 Gene-Disease associations (from GenCC):

• acrofacial dysostosis, Weyers type

  Inheritance: AD, AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae), G2P, Orphanet
• Ellis-van Creveld syndrome

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Myriad Women’s Health, Labcorp Genetics (formerly Invitae), Orphanet, Ambry Genetics, Laboratory for Molecular Medicine

ACMG classification

Our verdict: Uncertain_significance. The variant received 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.828

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_147127.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	EVC2	NM_147127.5	MANE Select	c.1195C>G	p.Arg399Gly	missense	Exon 10 of 22	NP_667338.3
	EVC2	NM_001166136.2		c.955C>G	p.Arg319Gly	missense	Exon 10 of 22	NP_001159608.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	EVC2	ENST00000344408.10	TSL:1 MANE Select	c.1195C>G	p.Arg399Gly	missense	Exon 10 of 22	ENSP00000342144.5
	EVC2	ENST00000310917.6	TSL:1	c.955C>G	p.Arg319Gly	missense	Exon 10 of 22	ENSP00000311683.2
	EVC2	ENST00000475313.5	TSL:1	n.955C>G		non_coding_transcript_exon	Exon 10 of 23	ENSP00000431981.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461882 Hom.: 0 Cov.: 34 AF XY: 0.00 AC XY: 0 AN XY: 727240

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 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: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86256

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53416

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

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1112006

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

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Ellis-van Creveld syndrome;C0457013:Curry-Hall syndrome Uncertain:1

Aug 21, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces arginine, which is basic and polar, with glycine, which is neutral and non-polar, at codon 399 of the EVC2 protein (p.Arg399Gly). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with EVC2-related conditions. An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests 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.

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.73
BayesDel_addAF	Pathogenic	0.40	D
BayesDel_noAF	Pathogenic	0.34
CADD	Uncertain	24
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.80	D
Eigen	Uncertain	0.51
Eigen_PC	Uncertain	0.40
FATHMM_MKL	Uncertain	0.89	D
LIST_S2	Benign	0.86	D
M_CAP	Pathogenic	0.33	D
MetaRNN	Pathogenic	0.83	D
MetaSVM	Uncertain	0.62	D
MutationAssessor	Uncertain	2.6	M
PhyloP100		3.5
PrimateAI	Benign	0.46	T
PROVEAN	Uncertain	-4.1	D
REVEL	Pathogenic	0.73
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.87
MutPred		0.50		Loss of ubiquitination at K404 (P = 0.0768)
MVP		0.93
MPC		0.18
ClinPred		1.0	D
GERP RS		4.2
Varity_R		0.51
gMVP		0.77
Mutation Taster		=48/52	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: rs137852924; hg19: chr4-5642516;