X-100408027-C-T

Variant names:

• chrX-100408027-C-T
• rs753757730
• NM_001184880.2:c.571G>A

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM1 PM2 PP2 PP3

The NM_001184880.2(PCDH19):​c.571G>A​(p.Val191Met) variant causes a missense change. The variant allele was found at a frequency of 0.000000914 in 1,094,096 control chromosomes in the GnomAD database, with no homozygous occurrence. There are no hemizygote samples in GnomAD. 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. V191L) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 25)
  • Exomes 𝑓: 9.1e-7 (0 hom. 0 hem.)
• Consequence: PCDH19 NM_001184880.2 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 6.17
• Publications: 7 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: Ambry Genetics, Orphanet, G2P, Labcorp Genetics (formerly Invitae)
• 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: Likely_pathogenic. The variant received 6 ACMG points.

• PM1: In a hotspot region, there are 5 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 8 uncertain in NM_001184880.2
• 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.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.76

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001184880.2. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	PCDH19	NM_001184880.2	MANE Select	c.571G>A	p.Val191Met	missense	Exon 1 of 6	NP_001171809.1	Q8TAB3-1
	PCDH19	NM_001105243.2		c.571G>A	p.Val191Met	missense	Exon 1 of 5	NP_001098713.1	Q8TAB3-2
	PCDH19	NM_020766.3		c.571G>A	p.Val191Met	missense	Exon 1 of 5	NP_065817.2	Q8TAB3-3

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	PCDH19	ENST00000373034.8	TSL:1 MANE Select	c.571G>A	p.Val191Met	missense	Exon 1 of 6	ENSP00000362125.4	Q8TAB3-1
	PCDH19	ENST00000255531.8	TSL:1	c.571G>A	p.Val191Met	missense	Exon 1 of 5	ENSP00000255531.7	Q8TAB3-2
	PCDH19	ENST00000420881.6	TSL:1	c.571G>A	p.Val191Met	missense	Exon 1 of 5	ENSP00000400327.2	Q8TAB3-3

Frequencies

GnomAD3 genomes Cov.: 25

GnomAD2 exomes AF: 0.00000562 AC: 1 AN: 177954 AF XY: 0.00

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 FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000123

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 9.14e-7 AC: 1 AN: 1094096 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 361536

⚠️ 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: 26401

American (AMR) AF: 0.00 AC: 0 AN: 35204

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 19386

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: 36473

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

European-Non Finnish (NFE) AF: 0.00000119 AC: 1 AN: 842070

Other (OTH) AF: 0.00 AC: 0 AN: 46073

⚠️ 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.: 25

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000756

ClinVar

ClinVar submissions

Significance: Uncertain significance

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
-	1	-	Developmental and epileptic encephalopathy, 9 (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.39
BayesDel_addAF	Pathogenic	0.27	D
BayesDel_noAF	Pathogenic	0.16
CADD	Uncertain	25
DANN	Uncertain	1.0
DEOGEN2	Benign	0.26	T
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Pathogenic	0.98	D
M_CAP	Pathogenic	0.30	D
MetaRNN	Pathogenic	0.76	D
MetaSVM	Benign	-0.31	T
MutationAssessor	Uncertain	2.8	M
PhyloP100		6.2
PrimateAI	Pathogenic	0.81	D
PROVEAN	Uncertain	-2.5	D
REVEL	Uncertain	0.33
Sift	Uncertain	0.020	D
Sift4G	Uncertain	0.029	D
Polyphen		1.0	D
Vest4		0.75
MutPred		0.51		Gain of disorder (P = 0.103)
MVP		0.78
MPC		2.3
ClinPred		0.86	D
GERP RS		5.8
Varity_R		0.81
gMVP		0.70
Mutation Taster		=14/86	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: rs753757730; hg19: chrX-99663025;