chr19-40396207-A-T

Variant names:

Variant summary

Our verdict is Pathogenic. Variant got 14 ACMG points: 14P and 0B. PVS1_StrongPM2PP5_Very_Strong

The NM_181882.3(PRX):c.2145T>A(p.Cys715*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000232 in 1,593,470 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★).

Frequency

Genomes: 𝑓 0.000053 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000021 ( 0 hom. )

Consequence

PRX
NM_181882.3 stop_gained

Scores

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:9O:1

Conservation

PhyloP100: -3.48

Variant links:

Genes affected

PRX (HGNC:13797): (periaxin) This gene encodes a protein involved in peripheral nerve myelin upkeep. The encoded protein contains 2 PDZ domains which were named after PSD95 (post synaptic density protein), DlgA (Drosophila disc large tumor suppressor), and ZO1 (a mammalian tight junction protein). Two alternatively spliced transcript variants have been described for this gene which encode different protein isoforms and which are targeted differently in the Schwann cell. Mutations in this gene cause Charcot-Marie-Tooth neuoropathy, type 4F and Dejerine-Sottas neuropathy. [provided by RefSeq, Jul 2008]

PRX links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 14 ACMG points.

PVS1

Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. There are 5 pathogenic variants in the truncated region.

PM2

Very rare variant in population databases, with high coverage;

PP5

Variant 19-40396207-A-T is Pathogenic according to our data. Variant chr19-40396207-A-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 4792.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr19-40396207-A-T is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
PRX	NM_181882.3 link	c.2145T>A	p.Cys715*	stop_gained	Exon 7 of 7	ENST00000324001.8	NP_870998.2	Q9BXM0-1
PRX	NM_001411127.1 link	c.2430T>A	p.Cys810*	stop_gained	Exon 7 of 7		NP_001398056.1
PRX	XM_017027047.2 link	c.2043T>A	p.Cys681*	stop_gained	Exon 4 of 4		XP_016882536.1
PRX	NM_020956.2 link	c.*2350T>A		3_prime_UTR_variant	Exon 6 of 6		NP_066007.1	Q9BXM0-2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
PRX	ENST00000324001.8 link	c.2145T>A	p.Cys715*	stop_gained	Exon 7 of 7	1	NM_181882.3	ENSP00000326018.6		Q9BXM0-1

Frequencies

GnomAD3 genomes

AF:

0.0000526

AC:

AN:

133170

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.000112

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.00000796

AC:

AN:

251342

Hom.:

AF XY:

0.00000736

AC XY:

AN XY:

135864

show subpopulations

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:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000176

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000205

AC:

AN:

1460188

Hom.:

Cov.:

AF XY:

0.0000151

AC XY:

AN XY:

726462

show subpopulations

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:

0.00

Gnomad4 FIN exome

AF:

0.0000375

Gnomad4 NFE exome

AF:

0.0000243

Gnomad4 OTH exome

AF:

0.0000166

GnomAD4 genome

AF:

0.0000525

AC:

AN:

133282

Hom.:

Cov.:

AF XY:

0.0000155

AC XY:

AN XY:

64708

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.000112

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000602

Hom.:

ExAC

AF:

0.0000165

AC:

EpiCase

AF:

0.000164

EpiControl

AF:

0.00

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:9Other:1

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not provided

Pathogenic:4

Jan 26, 2022

Revvity Omics, Revvity

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Oct 12, 2022

GeneDx

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Nonsense variant predicted to result in protein truncation, as the last 747 amino acids are lost, and other loss-of-function variants have been reported downstream in HGMD; Not observed at significant frequency in large population cohorts (gnomAD); This variant is associated with the following publications: (PMID: 12112076, 21840889, 20625412, 32085570) -

Nov 12, 2020

Athena Diagnostics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant is expected to result in the loss of a functional protein. The frequency of this variant in the general population is consistent with pathogenicity (http://gnomad.broadinstitute.org). This variant has been identified in at least one individual with clinical features associated with this gene. -

Apr 01, 2024

CeGaT Center for Human Genetics Tuebingen

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

PRX: PVS1:Strong, PM2, PM3 -

Charcot-Marie-Tooth disease type 4F

Pathogenic:2Other:1

Jun 01, 2002

OMIM

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: literature only

- -

Jul 26, 2022

MGZ Medical Genetics Center

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

GeneReviews

Significance: not provided

Review Status: no classification provided

Collection Method: literature only

- -

Charcot-Marie-Tooth disease

Pathogenic:1

Molecular Genetics Laboratory, London Health Sciences Centre

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Inborn genetic diseases

Pathogenic:1

Sep 23, 2019

Ambry Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.C715* variant (also known as c.2145T>A), located in coding exon 4 of the PRX gene, results from a T to A substitution at nucleotide position 2145. This changes the amino acid from a cysteine to a stop codon within coding exon 4. This alteration has been described homozygous in a brother and sister with Charcot-Marie-Tooth disease type 4F with disease onset prior to age 1 year and slow progression of disease. Additionally, unaffected siblings were either heterozygous or negative for the alteration (Takashima H et al. Ann. Neurol., 2002 Jun;51:709-15; Baets J et al. Brain, 2011 Sep;134:2664-76). Premature stop codons are typically deleterious in nature, however, this stop codon occurs at the 3' terminus of PRX, is not expected to trigger nonsense-mediated mRNA decay, and impacts the last 747 amino acids of the protein, which accounts for over 50% of the protein. Additional truncating alterations downstream of this alteration have been reported in the literature as disease-causing. In addition, the truncated region is suggested to be responsible for targeting the protein for ubiquitin-mediated proteolysis (Takashima H et al. Ann. Neurol., 2002 Jun;51:709-15). Studies in mice have also shown protein disruption when this C-terminal region is deleted (Sherman DL et al. Wellcome Open Res, 2018 Mar;3:20). As such, this alteration is interpreted as a disease-causing mutation. -

Charcot-Marie-Tooth disease type 4

Pathogenic:1

Sep 30, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change creates a premature translational stop signal (p.Cys715*) in the PRX gene. While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 747 amino acid(s) of the PRX protein. This variant is present in population databases (rs104894707, gnomAD 0.004%). This premature translational stop signal has been observed in individual(s) with Charcot-Marie-Tooth disease (PMID: 12112076). It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 4792). This variant disrupts a region of the PRX protein in which other variant(s) (p.Arg1070*) have been determined to be pathogenic (PMID: 15197604, 15469949, 16770524, 22847150, 26059842). This suggests that this is a clinically significant region of the protein, and that variants that disrupt it are likely to be disease-causing. For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_addAF

Benign

-0.13

BayesDel_noAF

Benign

-0.36

CADD

Benign

DANN

Benign

0.96

Eigen

Benign

-0.92

Eigen_PC

Benign

-1.4

FATHMM_MKL

Benign

0.028

Vest4

0.68

GERP RS

-8.4

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over