4-154604938-T-C

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_021870.3(FGG):c.1258A>G(p.Ile420Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000322 in 1,613,932 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: 𝑓 0.00013 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000022 (0 hom.)
• Consequence: FGG NM_021870.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.794

Genes affected

FGG (HGNC:3694): (fibrinogen gamma chain) The protein encoded by this gene is the gamma component of fibrinogen, a blood-borne glycoprotein comprised of three pairs of nonidentical polypeptide chains. Following vascular injury, fibrinogen is cleaved by thrombin to form fibrin which is the most abundant component of blood clots. In addition, various cleavage products of fibrinogen and fibrin regulate cell adhesion and spreading, display vasoconstrictor and chemotactic activities, and are mitogens for several cell types. Mutations in this gene lead to several disorders, including dysfibrinogenemia, hypofibrinogenemia and thrombophilia. Alternative splicing results in transcript variants encoding different isoforms. [provided by RefSeq, Aug 2015]

ACMG classification

Verdict is Uncertain_significance. Variant got 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.080355495).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
FGG	NM_021870.3	c.1258A>G	p.Ile420Val	missense_variant	9/9	ENST00000336098.8
FGG	NM_000509.6	c.1258A>G	p.Ile420Val	missense_variant	9/10

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
FGG	ENST00000336098.8	c.1258A>G	p.Ile420Val	missense_variant	9/9	2	NM_021870.3

Frequencies

GnomAD3 genomes AF: 0.000131 AC: 20 AN: 152114 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.000435

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: 0.000478

GnomAD3 exomes AF: 0.0000517 AC: 13 AN: 251412 Hom.: 0 AF XY: 0.0000368 AC XY: 5 AN XY: 135882

Gnomad AFR exome AF: 0.000738

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.0000544

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000219 AC: 32 AN: 1461818 Hom.: 0 Cov.: 34 AF XY: 0.0000179 AC XY: 13 AN XY: 727212

Gnomad4 AFR exome AF: 0.000448

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000252

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000135

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome AF: 0.000131 AC: 20 AN: 152114 Hom.: 0 Cov.: 32 AF XY: 0.000161 AC XY: 12 AN XY: 74310

Gnomad4 AFR AF: 0.000435

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000147

Gnomad4 OTH AF: 0.000478

Alfa AF: 0.0000644 Hom.: 0

Bravo AF: 0.000193

ESP6500AA AF: 0.000454 AC: 2

ESP6500EA AF: 0.00 AC: 0

ExAC AF: 0.0000330 AC: 4

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Congenital afibrinogenemia Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Mar 02, 2018

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.058
BayesDel_addAF	Benign	-0.20	T
BayesDel_noAF	Benign	-0.17
Cadd	Benign	14
Dann	Benign	0.96
Eigen	Benign	-0.43
Eigen_PC	Benign	-0.23
FATHMM_MKL	Benign	0.67	D
LIST_S2	Benign	0.84	T;T;T;T
M_CAP	Benign	0.061	D
MetaRNN	Benign	0.080	T;T;T;T
MetaSVM	Uncertain	-0.073	T
MutationAssessor	Benign	0.0	N;.;N;.
MutationTaster	Benign	1.0	N;N;N;N
PrimateAI	Benign	0.29	T
PROVEAN	Benign	0.090	N;N;N;N
REVEL	Uncertain	0.30
Sift	Benign	0.38	T;T;T;T
Sift4G	Benign	1.0	T;T;T;T
Polyphen		0.0	B;B;B;B
Vest4		0.10
MVP		0.83
MPC		0.17
ClinPred		0.024	T
GERP RS		5.7
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
Varity_R		0.23
gMVP		0.70

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: rs374917187; hg19: chr4-155526090;