8-74360293-C-T

Variant names:

• chr8-74360293-C-T
• rs397515441
• NM_018972.4:c.467C>T

Variant summary

Our verdict is Likely pathogenic. The variant received 9 ACMG points: 9P and 0B. PM1 PM2 PM5 PP2 PP3_Moderate

The NM_018972.4(GDAP1):​c.467C>T​(p.Ala156Val) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,314 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. A156S) has been classified as Likely pathogenic.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: GDAP1 NM_018972.4 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 7.53
• Publications: 4 publications found

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 Gene-Disease associations (from GenCC):

• Charcot-Marie-Tooth disease

  Inheritance: SD Classification: DEFINITIVE Submitted by: ClinGen
• Charcot-Marie-Tooth disease axonal type 2K

  Inheritance: AD, AR Classification: STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Orphanet
• Charcot-Marie-Tooth disease recessive intermediate A

  Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Orphanet
• autosomal dominant Charcot-Marie-Tooth disease type 2K

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• Charcot-Marie-Tooth disease type 4A

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_pathogenic. The variant received 9 ACMG points.

• PM1: In a hotspot region, there are 6 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 11 uncertain in NM_018972.4
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr8-74360292-G-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 1043085.
• PP2: Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 32 curated pathogenic missense variants (we use a threshold of 10). The gene has 3 curated benign missense variants. Gene score misZ: 1.0 (below the threshold of 3.09). Trascript score misZ: 1.1646 (below the threshold of 3.09). GenCC associations: The gene is linked to Charcot-Marie-Tooth disease axonal type 2K, Charcot-Marie-Tooth disease recessive intermediate A, Charcot-Marie-Tooth disease type 4A, Charcot-Marie-Tooth disease, autosomal dominant Charcot-Marie-Tooth disease type 2K.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.891

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
GDAP1	NM_018972.4	c.467C>T	p.Ala156Val	missense_variant	Exon 3 of 6	ENST00000220822.12	NP_061845.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
GDAP1	ENST00000220822.12	c.467C>T	p.Ala156Val	missense_variant	Exon 3 of 6	1	NM_018972.4	ENSP00000220822.7

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461314 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 726992

African (AFR) AF: 0.00 AC: 0 AN: 33466

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26128

East Asian (EAS) AF: 0.0000252 AC: 1 AN: 39692

South Asian (SAS) AF: 0.00 AC: 0 AN: 86244

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53412

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111498

Other (OTH) AF: 0.00 AC: 0 AN: 60382

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.89
BayesDel_addAF	Pathogenic	0.37	D
BayesDel_noAF	Pathogenic	0.29
CADD	Pathogenic	30
DANN	Pathogenic	1.0
DEOGEN2	Benign	0.14	T;.
Eigen	Uncertain	0.63
Eigen_PC	Uncertain	0.64
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.96	D;D
M_CAP	Pathogenic	0.32	D
MetaRNN	Pathogenic	0.89	D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Benign	2.0	M;.
PhyloP100		7.5
PrimateAI	Pathogenic	0.83	D
PROVEAN	Benign	-0.90	N;N
REVEL	Pathogenic	0.75
Sift	Benign	0.030	D;D
Sift4G	Pathogenic	0.0	D;D
Polyphen		0.97	D;.
Vest4		0.83
MutPred		0.72		Loss of disorder (P = 0.1355);.;
MVP		0.99
MPC		1.3
ClinPred		0.74	D
GERP RS		5.5
Varity_R		0.20
gMVP		0.79
Mutation Taster		=18/82	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.26		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.26		Position offset: -2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs397515441; hg19: chr8-75272528;