12-32640429-A-G

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM2BP4_Moderate

The NM_001370298.3(FGD4):​c.2608A>G​(p.Lys870Glu) variant causes a missense change. The variant allele was found at a frequency of 0.0000372 in 1,614,002 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/22 in silico tools predict 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. K870N) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000040 ( 0 hom. )

Consequence

FGD4
NM_001370298.3 missense

Scores

3
15

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 4.60

Publications

0 publications found
Variant links:
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

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 0 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.15987304).

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

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
FGD4
NM_001370298.3
MANE Select
c.2608A>Gp.Lys870Glu
missense
Exon 17 of 17NP_001357227.2
FGD4
NM_001384126.1
c.2608A>Gp.Lys870Glu
missense
Exon 17 of 18NP_001371055.1
FGD4
NM_001304481.2
c.2452A>Gp.Lys818Glu
missense
Exon 17 of 17NP_001291410.1

Ensembl Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
FGD4
ENST00000534526.7
TSL:5 MANE Select
c.2608A>Gp.Lys870Glu
missense
Exon 17 of 17ENSP00000449273.1
FGD4
ENST00000531134.7
TSL:2
c.2452A>Gp.Lys818Glu
missense
Exon 17 of 17ENSP00000431323.1
FGD4
ENST00000427716.7
TSL:2
c.2197A>Gp.Lys733Glu
missense
Exon 18 of 18ENSP00000394487.2

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152116
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
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:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000438
AC:
11
AN:
251226
AF XY:
0.0000737
show subpopulations
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:
0.0000969
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000404
AC:
59
AN:
1461886
Hom.:
0
Cov.:
31
AF XY:
0.0000344
AC XY:
25
AN XY:
727246
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.0000224
AC:
1
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39698
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000522
AC:
58
AN:
1112006
Other (OTH)
AF:
0.00
AC:
0
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.477
Heterozygous variant carriers
0
6
12
17
23
29
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152116
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74316
show subpopulations
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.00
AC:
0
AN:
41434
American (AMR)
AF:
0.00
AC:
0
AN:
15282
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5176
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4828
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10606
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68004
Other (OTH)
AF:
0.00
AC:
0
AN:
2086
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.375
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.0000868
Hom.:
0
Bravo
AF:
0.0000189
ExAC
AF:
0.0000741
AC:
9
EpiCase
AF:
0.000164
EpiControl
AF:
0.000178

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Inborn genetic diseases Uncertain:1
Sep 14, 2021
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.2197A>G (p.K733E) alteration is located in exon 17 (coding exon 15) of the FGD4 gene. This alteration results from a A to G substitution at nucleotide position 2197, causing the lysine (K) at amino acid position 733 to be replaced by a glutamic acid (E). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear.

Charcot-Marie-Tooth disease type 4 Uncertain:1
Aug 10, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces lysine, which is basic and polar, with glutamic acid, which is acidic and polar, at codon 733 of the FGD4 protein (p.Lys733Glu). This variant is present in population databases (rs746459196, gnomAD 0.009%). This variant has not been reported in the literature in individuals affected with FGD4-related conditions. ClinVar contains an entry for this variant (Variation ID: 577465). 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 FGD4 protein function. 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.

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.090
BayesDel_addAF
Benign
-0.15
T
BayesDel_noAF
Benign
-0.25
CADD
Benign
23
DANN
Uncertain
0.99
DEOGEN2
Benign
0.14
T
Eigen
Benign
-0.22
Eigen_PC
Benign
-0.063
FATHMM_MKL
Uncertain
0.96
D
LIST_S2
Uncertain
0.89
D
M_CAP
Benign
0.0063
T
MetaRNN
Benign
0.16
T
MetaSVM
Benign
-1.1
T
MutationAssessor
Benign
0.91
L
PhyloP100
4.6
PrimateAI
Benign
0.47
T
PROVEAN
Benign
-0.73
N
REVEL
Benign
0.20
Sift
Benign
0.58
T
Sift4G
Benign
0.87
T
Polyphen
0.12
B
Vest4
0.38
MutPred
0.56
Loss of ubiquitination at K845 (P = 0.0255)
MVP
0.57
MPC
0.52
ClinPred
0.12
T
GERP RS
4.1
Varity_R
0.14
gMVP
0.40
Mutation Taster
=68/32
polymorphism

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

Publications

Other links and lift over

dbSNP: rs746459196; hg19: chr12-32793363; API