rs1554548334

Positions:

• chr8-74363993-C-T

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PVS1 PM2 PP5_Moderate

The NM_018972.4(GDAP1):​c.703C>T​(p.Gln235Ter) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: GDAP1 NM_018972.4 stop_gained
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 0.376

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]

ACMG classification

Verdict is Pathogenic. Variant got 12 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 43 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 8-74363993-C-T is Pathogenic according to our data. Variant chr8-74363993-C-T is described in ClinVar as [Pathogenic]. Clinvar id is 467768.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
GDAP1	NM_018972.4	c.703C>T	p.Gln235Ter	stop_gained	6/6	ENST00000220822.12

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
GDAP1	ENST00000220822.12	c.703C>T	p.Gln235Ter	stop_gained	6/6	1	NM_018972.4	P3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Charcot-Marie-Tooth disease type 4A Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Nov 08, 2022

For these reasons, this variant has been classified as Pathogenic. This variant disrupts a region of the GDAP1 protein in which other variant(s) (p.Phe263Leufs*22) have been determined to be pathogenic (PMID: 12499475). This suggests that this is a clinically significant region of the protein, and that variants that disrupt it are likely to be disease-causing. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. ClinVar contains an entry for this variant (Variation ID: 467768). This premature translational stop signal has been observed in individuals with Charcot-Marie-Tooth disease (PMID: 28751717). This variant is not present in population databases (gnomAD no frequency). This sequence change creates a premature translational stop signal (p.Gln235*) in the GDAP1 gene. While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 124 amino acid(s) of the GDAP1 protein. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.45
CADD	Pathogenic	36
DANN	Uncertain	1.0
Eigen	Uncertain	0.60
Eigen_PC	Uncertain	0.42
FATHMM_MKL	Benign	0.59	D
MutationTaster	Benign	1.0	D;D
Vest4		0.50
GERP RS		3.1
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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

Other links and lift over

dbSNP: rs1554548334; hg19: chr8-75276228; COSMIC: COSV99619688; COSMIC: COSV99619688;