12-32602217-T-C

Position:

• chr12-32602217-T-C

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2 PM5 PP3_Moderate

The NM_001370298.3(FGD4):​c.1304T>C​(p.Met435Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,736 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. M435R) has been classified as Pathogenic.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: FGD4 NM_001370298.3 missense
• Clinical Significance: Conflicting classifications of pathogenicity no assertion criteria provided P:1 U:2 O:1
• Conservation: PhyloP100: 7.75

Genes affected

FGD4 (HGNC:19125): (FYVE, RhoGEF and PH domain containing 4) This gene encodes a protein that is involved in the regulation of the actin cytoskeleton and cell shape. This protein contains an actin filament-binding domain, which together with its Dbl homology domain and one of its pleckstrin homology domains, can form microspikes. This protein can activate MAPK8 independently of the actin filament-binding domain, and it is also involved in the activation of CDC42 via the exchange of bound GDP for free GTP. The activation of CDC42 also enables this protein to play a role in mediating the cellular invasion of Cryptosporidium parvum, an intracellular parasite that infects the gastrointestinal tract. Mutations in this gene can cause Charcot-Marie-Tooth disease type 4H (CMT4H), a disorder of the peripheral nervous system. Multiple alternatively spliced transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jan 2015]

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr12-32602217-T-G is described in Lovd as [Pathogenic].
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.86

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
FGD4	NM_001370298.3	c.1304T>C	p.Met435Thr	missense_variant	7/17	ENST00000534526.7	NP_001357227.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
FGD4	ENST00000534526.7	c.1304T>C	p.Met435Thr	missense_variant	7/17	5	NM_001370298.3	ENSP00000449273

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251422 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 135890

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: 0.00000879

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461736 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 727174

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: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 33

Alfa AF: 0.0000508 Hom.: 0

Bravo AF: 0.00000378

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:1 Uncertain:2 Other:1

Revision: no assertion criteria provided

Submissions by phenotype

Charcot-Marie-Tooth disease type 4H Pathogenic:1 Uncertain:1 Other:1

Uncertain significance, no assertion criteria provided	literature only	Inherited Neuropathy Consortium Ii, University Of Miami	Jan 06, 2016	- -
Pathogenic, no assertion criteria provided	literature only	OMIM	Jul 01, 2007	- -
not provided, no classification provided	literature only	GeneReviews	-	- -

Charcot-Marie-Tooth disease Uncertain:1

Uncertain significance, no assertion criteria provided

literature only

Inherited Neuropathy Consortium

-

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.36	D
BayesDel_noAF	Pathogenic	0.29
CADD	Pathogenic	26
DANN	Uncertain	0.99
DEOGEN2	Benign	0.21	T;T;T;T;T
Eigen	Pathogenic	0.77
Eigen_PC	Pathogenic	0.73
FATHMM_MKL	Pathogenic	1.0	D
LIST_S2	Pathogenic	0.99	D;D;D;D;D
M_CAP	Uncertain	0.094	D
MetaRNN	Pathogenic	0.86	D;D;D;D;D
MetaSVM	Uncertain	0.024	D
MutationAssessor	Uncertain	2.5	.;.;M;.;.
MutationTaster	Benign	1.0	D;D;D;D;D;D;D
PrimateAI	Pathogenic	0.92	D
PROVEAN	Pathogenic	-5.8	D;D;D;D;D
REVEL	Pathogenic	0.80
Sift	Pathogenic	0.0	D;D;D;D;D
Sift4G	Pathogenic	0.0010	D;D;D;D;D
Polyphen		0.97, 1.0, 1.0	.;D;D;.;D
Vest4		0.95
MutPred		0.75		.;.;.;.;Gain of methylation at K409 (P = 0.0505);
MVP		0.85
MPC		1.1
ClinPred		0.99	D
GERP RS		5.0
Varity_R		0.97
gMVP		0.83

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

Other links and lift over

dbSNP: rs63749871; hg19: chr12-32755151;