8-74361955-A-G

Position:

chr8-74361955-A-G

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 4P and 2B. PM1PM2BP4_Moderate

The NM_018972.4(GDAP1):c.556A>G(p.Ile186Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000755 in 1,598,174 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts 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. I186T) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.00041 ( 0 hom., cov: 33)

Exomes 𝑓: 0.00079 ( 1 hom. )

Consequence

GDAP1
NM_018972.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:10

Conservation

PhyloP100: 0.888

Variant links:

Genes affected

GDAP1 (HGNC:15968): (ganglioside induced differentiation associated protein 1) This gene encodes a member of the ganglioside-induced differentiation-associated protein family, which may play a role in a signal transduction pathway during neuronal development. Mutations in this gene have been associated with various forms of Charcot-Marie-Tooth Disease and neuropathy. Two transcript variants encoding different isoforms and a noncoding variant have been identified for this gene. [provided by RefSeq, Feb 2012]

GDAP1 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 2 ACMG points.

PM1

In a domain GST C-terminal (size 156) in uniprot entity GDAP1_HUMAN there are 54 pathogenic changes around while only 0 benign (100%) in NM_018972.4

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (MetaRNN=0.08695093).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
GDAP1	NM_018972.4 linkuse as main transcript	c.556A>G	p.Ile186Val	missense_variant	4/6	ENST00000220822.12

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
GDAP1	ENST00000220822.12 linkuse as main transcript	c.556A>G	p.Ile186Val	missense_variant	4/6	1	NM_018972.4	P3	Q8TB36-1

Frequencies

GnomAD3 genomes

AF:

0.000407

AC:

AN:

152250

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.000217

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.000458

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:

0.000676

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.000332

AC:

AN:

249790

Hom.:

AF XY:

0.000362

AC XY:

AN XY:

135210

show subpopulations

Gnomad AFR exome

AF:

0.0000617

Gnomad AMR exome

AF:

0.000347

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:

0.000599

Gnomad OTH exome

AF:

0.000327

GnomAD4 exome

AF:

0.000792

AC:

1145

AN:

1445806

Hom.:

Cov.:

AF XY:

0.000780

AC XY:

562

AN XY:

720302

show subpopulations

Gnomad4 AFR exome

AF:

0.0000902

Gnomad4 AMR exome

AF:

0.000380

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00101

Gnomad4 OTH exome

AF:

0.000317

GnomAD4 genome

AF:

0.000407

AC:

AN:

152368

Hom.:

Cov.:

AF XY:

0.000376

AC XY:

AN XY:

74506

show subpopulations

Gnomad4 AFR

AF:

0.000216

Gnomad4 AMR

AF:

0.000457

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.000676

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.000638

Hom.:

Bravo

AF:

0.000465

TwinsUK

AF:

0.000539

AC:

ALSPAC

AF:

0.00182

AC:

ESP6500AA

AF:

0.000227

AC:

ESP6500EA

AF:

0.00105

AC:

ExAC

AF:

0.000346

AC:

EpiCase

AF:

0.000327

EpiControl

AF:

0.000356

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:10

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not provided

Uncertain:5

Uncertain significance, criteria provided, single submitter	clinical testing	Greenwood Genetic Center Diagnostic Laboratories, Greenwood Genetic Center	Jun 01, 2022	No Applicable ACMG Criteria -
Uncertain significance, criteria provided, single submitter	clinical testing	Mayo Clinic Laboratories, Mayo Clinic	Mar 31, 2021	- -
Uncertain significance, criteria provided, single submitter	clinical testing	GeneDx	Aug 30, 2023	Reported previously as a variant of uncertain significance in two patients with a clinical diagnosis of Charcot-Marie-Tooth disease; however, clinical and segregation information was not provided (Volodarsky et al., 2021); In silico analysis supports that this missense variant does not alter protein structure/function; This variant is associated with the following publications: (PMID: 32376792, 20849849) -
Uncertain significance, criteria provided, single submitter	clinical testing	ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories	Sep 11, 2023	The GDAP1 c.556A>G; p.Ile186Val variant (rs148508128) is reported in the literature in individuals with suspected CMT, but without evidence for pathogenicity (Volodarsky 2021). This variant is reported in ClinVar (Variation ID: 216707) and is found in the non-Finnish European population with an allele frequency of 0.06% (73/129024 alleles) in the Genome Aggregation Database. Computational analyses are uncertain whether this variant is neutral or deleterious (REVEL: 0.354). Due to limited information, the clinical significance of the p.Ile186Val variant is uncertain at this time. References: Volodarsky M et al. Comprehensive genetic sequence and copy number analysis for Charcot-Marie-Tooth disease in a Canadian cohort of 2517 patients. J Med Genet. 2021 Apr;58(4):284-288. PMID: 32376792. -
Uncertain significance, criteria provided, single submitter	clinical testing	CeGaT Center for Human Genetics Tuebingen	Sep 01, 2023	GDAP1: PM2:Supporting -

Charcot-Marie-Tooth disease recessive intermediate A

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 13, 2018

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Inborn genetic diseases

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Jan 03, 2023

Unlikely to be causative of GDAP1-related Charcot-Marie-Tooth disease, type 2 (AD) Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Charcot-Marie-Tooth disease type 4A

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jan 19, 2024

This sequence change replaces isoleucine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 186 of the GDAP1 protein (p.Ile186Val). This variant is present in population databases (rs148508128, gnomAD 0.06%). This missense change has been observed in individual(s) with clinical features of Charcot-Marie-Tooth disease (PMID: 32376792). ClinVar contains an entry for this variant (Variation ID: 216707). 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 GDAP1 protein function with a negative predictive value of 80%. 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. -

Charcot-Marie-Tooth disease, axonal, with vocal cord paresis, autosomal recessive

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 13, 2018

Charcot-Marie-Tooth disease recessive intermediate A;C1842983:Charcot-Marie-Tooth disease axonal type 2K;C1843183:Charcot-Marie-Tooth disease, axonal, with vocal cord paresis, autosomal recessive;C1859198:Charcot-Marie-Tooth disease type 4A

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Fulgent Genetics, Fulgent Genetics

Nov 17, 2021

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.062

BayesDel_addAF

Benign

-0.20

BayesDel_noAF

Uncertain

-0.070

CADD

Benign

DANN

Uncertain

0.99

DEOGEN2

Benign

0.11

T;.

Eigen

Benign

-0.27

Eigen_PC

Benign

-0.072

FATHMM_MKL

Uncertain

0.85

LIST_S2

Benign

0.84

T;T

M_CAP

Uncertain

0.19

MetaRNN

Benign

0.087

T;T

MetaSVM

Uncertain

0.77

MutationAssessor

Benign

0.34

N;.

MutationTaster

Benign

0.98

D;D

PrimateAI

Uncertain

0.68

PROVEAN

Benign

-0.24

N;N

REVEL

Uncertain

0.35

Sift

Benign

0.078

T;T

Sift4G

Uncertain

0.024

D;D

Polyphen

0.0020

B;.

Vest4

0.31

MVP

0.88

MPC

0.38

ClinPred

0.024

GERP RS

5.3

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Varity_R

0.045

gMVP

0.44

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