12-32602279-C-G

Variant names:

• chr12-32602279-C-G
• rs1131691854
• NM_001370298.3:c.1366C>G

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2

The NM_001370298.3(FGD4):​c.1366C>G​(p.Arg456Gly) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,812 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. R456C) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: FGD4 NM_001370298.3 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 1.78
• Publications: 0 publications found

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]

FGD4 Gene-Disease associations (from GenCC):

• Charcot-Marie-Tooth disease

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
• Charcot-Marie-Tooth disease type 4H

  Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Orphanet

ACMG classification

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001370298.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	FGD4	NM_001370298.3	MANE Select	c.1366C>G	p.Arg456Gly	missense	Exon 7 of 17	NP_001357227.2	F8VWL3
	FGD4	NM_001384126.1		c.1366C>G	p.Arg456Gly	missense	Exon 7 of 18	NP_001371055.1
	FGD4	NM_001304481.2		c.1210C>G	p.Arg404Gly	missense	Exon 7 of 17	NP_001291410.1	B7Z493

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	FGD4	ENST00000534526.7	TSL:5 MANE Select	c.1366C>G	p.Arg456Gly	missense	Exon 7 of 17	ENSP00000449273.1	F8VWL3
	FGD4	ENST00000395740.5	TSL:1	n.*347C>G		non_coding_transcript_exon	Exon 8 of 17	ENSP00000379089.1	E9PNX0
	FGD4	ENST00000395740.5	TSL:1	n.*347C>G		3_prime_UTR	Exon 8 of 17	ENSP00000379089.1	E9PNX0

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD2 exomes AF: 0.00000398 AC: 1 AN: 251446 AF XY: 0.00

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 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: 1461812 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 727208

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44722

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26134

East Asian (EAS) AF: 0.00 AC: 0 AN: 39668

South Asian (SAS) AF: 0.00 AC: 0 AN: 86256

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53416

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

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1111976

Other (OTH) AF: 0.00 AC: 0 AN: 60392

GnomAD4 genome Cov.: 33

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.38
BayesDel_addAF	Uncertain	0.080	D
BayesDel_noAF	Benign	-0.12
CADD	Pathogenic	28
DANN	Uncertain	1.0
DEOGEN2	Benign	0.11	T
Eigen	Uncertain	0.50
Eigen_PC	Uncertain	0.44
FATHMM_MKL	Uncertain	0.94	D
LIST_S2	Pathogenic	0.98	D
M_CAP	Benign	0.025	T
MetaRNN	Uncertain	0.49	T
MetaSVM	Benign	-0.83	T
MutationAssessor	Uncertain	2.1	M
PhyloP100		1.8
PrimateAI	Uncertain	0.56	T
PROVEAN	Pathogenic	-6.2	D
REVEL	Benign	0.27
Sift	Uncertain	0.0010	D
Sift4G	Uncertain	0.0020	D
Polyphen		0.91	P
Vest4		0.57
MutPred		0.51		Gain of catalytic residue at I432 (P = 0.0054)
MVP		0.71
MPC		1.2
ClinPred		0.99	D
GERP RS		3.9
Varity_R		0.92
gMVP		0.67
Mutation Taster		=50/50

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.090		Details are displayed if max score is > 0.2

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

Other links and lift over

dbSNP: rs1131691854; hg19: chr12-32755213;