chrX-100408270-T-C

Variant names:

• chrX-100408270-T-C
• rs1057520139
• NM_001184880.2:c.328A>G

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 3P and 1B. PM2 PP2 BP4

The NM_001184880.2(PCDH19):​c.328A>G​(p.Met110Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000182 in 1,098,089 control chromosomes in the GnomAD database, with no homozygous occurrence. There are no hemizygote samples in GnomAD. In-silico tool predicts a benign outcome for this variant. 13/21 in silico tools predict a benign 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. M110I) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 24)
  • Exomes 𝑓: 0.0000018 (0 hom. 0 hem.)
• Consequence: PCDH19 NM_001184880.2 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 3.38
• Publications: 0 publications found

Genes affected

PCDH19 (HGNC:14270): (protocadherin 19) The protein encoded by this gene is a member of the delta-2 protocadherin subclass of the cadherin superfamily. The encoded protein is thought to be a calcium-dependent cell-adhesion protein that is primarily expressed in the brain. Mutations in this gene on human chromosome X are associated with sporadic infantile epileptic encephalopathy and to a female-restricted form of epilepsy (EFMR; also known as PCDH19RE). Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jul 2017]

PCDH19 Gene-Disease associations (from GenCC):

• developmental and epileptic encephalopathy, 9

  Inheritance: XL, Unknown Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: G2P, Orphanet, Labcorp Genetics (formerly Invitae), Ambry Genetics
• X-linked complex neurodevelopmental disorder

  Inheritance: XL Classification: DEFINITIVE Submitted by: ClinGen
• Dravet syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Uncertain_significance. The variant received 2 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 107 curated pathogenic missense variants (we use a threshold of 10). The gene has 20 curated benign missense variants. Gene score misZ: 2.5929 (below the threshold of 3.09). Trascript score misZ: NaN (below the threshold of 3.09). GenCC associations: The gene is linked to Dravet syndrome, developmental and epileptic encephalopathy, 9, X-linked complex neurodevelopmental disorder.
• BP4: Computational evidence support a benign effect (MetaRNN=0.35633904).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
PCDH19	NM_001184880.2	c.328A>G	p.Met110Val	missense_variant	Exon 1 of 6	ENST00000373034.8	NP_001171809.1
PCDH19	NM_001105243.2	c.328A>G	p.Met110Val	missense_variant	Exon 1 of 5		NP_001098713.1
PCDH19	NM_020766.3	c.328A>G	p.Met110Val	missense_variant	Exon 1 of 5		NP_065817.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
PCDH19	ENST00000373034.8	c.328A>G	p.Met110Val	missense_variant	Exon 1 of 6	1	NM_001184880.2	ENSP00000362125.4
PCDH19	ENST00000255531.8	c.328A>G	p.Met110Val	missense_variant	Exon 1 of 5	1		ENSP00000255531.7
PCDH19	ENST00000420881.6	c.328A>G	p.Met110Val	missense_variant	Exon 1 of 5	1		ENSP00000400327.2

Frequencies

GnomAD3 genomes Cov.: 24

GnomAD4 exome AF: 0.00000182 AC: 2 AN: 1098089 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 363443

African (AFR) AF: 0.00 AC: 0 AN: 26400

American (AMR) AF: 0.0000284 AC: 1 AN: 35207

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 19385

East Asian (EAS) AF: 0.00 AC: 0 AN: 30206

South Asian (SAS) AF: 0.00 AC: 0 AN: 54146

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 40493

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 4137

European-Non Finnish (NFE) AF: 0.00000119 AC: 1 AN: 842023

Other (OTH) AF: 0.00 AC: 0 AN: 46092

GnomAD4 genome Cov.: 24

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Uncertain:1

May 20, 2016

Center for Pediatric Genomic Medicine, Children's Mercy Hospital and Clinics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Developmental and epileptic encephalopathy, 9 Uncertain:1

May 08, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces methionine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 110 of the PCDH19 protein (p.Met110Val). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with PCDH19-related conditions. ClinVar contains an entry for this variant (Variation ID: 377119). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt PCDH19 protein function with a negative predictive value of 95%. 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 v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.55
BayesDel_addAF	Benign	-0.17	T
BayesDel_noAF	Benign	-0.48
CADD	Benign	22
DANN	Benign	0.97
DEOGEN2	Benign	0.057	.;T;.
FATHMM_MKL	Uncertain	0.89	D
LIST_S2	Uncertain	0.89	D;D;D
M_CAP	Benign	0.013	T
MetaRNN	Benign	0.36	T;T;T
MetaSVM	Benign	-1.1	T
MutationAssessor	Benign	0.90	L;L;L
PhyloP100		3.4
PrimateAI	Uncertain	0.58	T
PROVEAN	Benign	-1.3	N;N;N
REVEL	Benign	0.10
Sift	Uncertain	0.028	D;D;D
Sift4G	Benign	0.15	T;T;T
Polyphen		0.14, 0.061	.;B;B
Vest4		0.59
MutPred		0.45		Loss of catalytic residue at M110 (P = 0.1193);Loss of catalytic residue at M110 (P = 0.1193);Loss of catalytic residue at M110 (P = 0.1193);
MVP		0.41
MPC		1.3
ClinPred		0.51	D
GERP RS		4.5
PromoterAI		0.0018	Neutral
Varity_R		0.81
gMVP		0.63
Mutation Taster		=70/30	polymorphism

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: rs1057520139; hg19: chrX-99663268;