NM_004463.3:c.2773T>G

Variant names:

• chrX-54446222-A-C
• rs1922168917
• NM_004463.3:c.2773T>G

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 3P and 2B. PM2 PP2 BP4_Moderate

The NM_004463.3(FGD1):​c.2773T>G​(p.Phe925Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000273 in 1,097,720 control chromosomes in the GnomAD database, with no homozygous occurrence. There are 1 hemizygotes in GnomAD. In-silico tool predicts a benign outcome for this variant. 14/20 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: not found (cov: 23)
  • Exomes 𝑓: 0.0000027 (0 hom. 1 hem.)
• Consequence: FGD1 NM_004463.3 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 2.20

Genes affected

FGD1 (HGNC:3663): (FYVE, RhoGEF and PH domain containing 1) This gene encodes a protein that contains Dbl (DH) and pleckstrin (PH) homology domains and is similar to the Rho family of small GTP-binding proteins. The encoded protein specifically binds to the Rho family GTPase Cdc42Hs and can stimulate the GDP-GTP exchange of the isoprenylated form of Cdc42Hs. It also stimulates the mitogen activated protein kinase cascade leading to c-Jun kinase SAPK/JNK1 activation. Defects in this gene are the cause of the faciogenital dysplasia in Aarskog-Scott syndrome and a syndromatic form of X-linked cognitive disability. [provided by RefSeq, Jul 2017]

TSR2 (HGNC:25455): (TSR2 ribosome maturation factor) The protein encoded by this gene appears to repress the transcription of NF-kappaB and may be involved in apoptosis. Defects in this gene are a cause of Diamond-Blackfan anemia. [provided by RefSeq, Oct 2016]

ACMG classification

Verdict is Uncertain_significance. Variant got 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in the FGD1 gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 11 curated pathogenic missense variants (we use a threshold of 10). The gene has 24 curated benign missense variants. Gene score misZ: 3.5183 (above the threshold of 3.09). GenCC associations: The gene is linked to Aarskog-Scott syndrome, X-linked.
• BP4: Computational evidence support a benign effect (MetaRNN=0.12881157).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
FGD1	NM_004463.3	c.2773T>G	p.Phe925Val	missense_variant	Exon 18 of 18	ENST00000375135.4	NP_004454.2
TSR2	NM_058163.3	c.*1672A>C		3_prime_UTR_variant	Exon 5 of 5	ENST00000375151.5	NP_477511.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
FGD1	ENST00000375135.4	c.2773T>G	p.Phe925Val	missense_variant	Exon 18 of 18	1	NM_004463.3	ENSP00000364277.3
TSR2	ENST00000375151.5	c.*1672A>C		3_prime_UTR_variant	Exon 5 of 5	1	NM_058163.3	ENSP00000364293.4

Frequencies

GnomAD3 genomes Cov.: 23

GnomAD4 exome AF: 0.00000273 AC: 3 AN: 1097720 Hom.: 0 Cov.: 31 AF XY: 0.00000275 AC XY: 1 AN XY: 363118

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: 0.00000119

Gnomad4 OTH exome AF: 0.0000217

GnomAD4 genome Cov.: 23

Bravo AF: 0.0000151

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Uncertain:2

Jun 12, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces phenylalanine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 925 of the FGD1 protein (p.Phe925Val). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with FGD1-related conditions. ClinVar contains an entry for this variant (Variation ID: 2660662). 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 expected to disrupt FGD1 protein function with a positive predictive value of 80%. 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. -

Jul 01, 2022

CeGaT Center for Human Genetics Tuebingen

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

FGD1: PM2, PP2 -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.12
BayesDel_addAF	Benign	-0.20	T
BayesDel_noAF	Benign	-0.52
CADD	Benign	19
DANN	Benign	0.96
DEOGEN2	Benign	0.083	T
FATHMM_MKL	Benign	0.70	D
LIST_S2	Benign	0.73	T
M_CAP	Benign	0.017	T
MetaRNN	Benign	0.13	T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	0.55	N
PrimateAI	Uncertain	0.56	T
PROVEAN	Benign	-0.62	N
REVEL	Benign	0.042
Sift	Benign	0.24	T
Sift4G	Benign	0.50	T
Polyphen		0.069	B
Vest4		0.27
MutPred		0.16		Gain of catalytic residue at F925 (P = 0.0621);
MVP		0.65
MPC		1.5
ClinPred		0.17	T
GERP RS		3.1
Varity_R		0.16
gMVP		0.51

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: rs1922168917; hg19: chrX-54472655;