NM_021870.3:c.667-320A>T

Variant names:

• chr4-154608970-T-A
• rs587776839
• NM_021870.3:c.667-320A>T

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PM2 PP3 PP5

The NM_021870.3(FGG):​c.667-320A>T variant causes a intron change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Pathogenic (no stars).

• Frequency: Genomes: not found (cov: 32)
• Consequence: FGG NM_021870.3 intron
• Clinical Significance: Pathogenic no assertion criteria provided P:1
• Conservation: PhyloP100: 0.890
• Publications: 0 publications found

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]

FGG Gene-Disease associations (from GenCC):

• congenital fibrinogen deficiency

  Inheritance: SD Classification: DEFINITIVE Submitted by: ClinGen
• familial dysfibrinogenemia

  Inheritance: AD Classification: STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Orphanet
• thrombophilia

  Inheritance: AD, AR Classification: STRONG Submitted by: Genomics England PanelApp
• congenital afibrinogenemia

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

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Uncertain_significance. The variant received 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.
• PP5: Variant 4-154608970-T-A is Pathogenic according to our data. Variant chr4-154608970-T-A is described in ClinVar as Pathogenic. ClinVar VariationId is 16380.Status of the report is no_assertion_criteria_provided, 0 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_021870.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	FGG	NM_021870.3	MANE Select	c.667-320A>T		intron	N/A	NP_068656.2
	FGG	NM_000509.6		c.667-320A>T		intron	N/A	NP_000500.2

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	FGG	ENST00000336098.8	TSL:2 MANE Select	c.667-320A>T		intron	N/A	ENSP00000336829.3
	FGG	ENST00000404648.7	TSL:1	c.667-320A>T		intron	N/A	ENSP00000384860.3
	FGG	ENST00000407946.5	TSL:5	c.691-320A>T		intron	N/A	ENSP00000384552.1

Frequencies

GnomAD3 genomes Cov.: 32

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: no assertion criteria provided

Submissions by phenotype

Congenital afibrinogenemia Pathogenic:1

Oct 01, 2007

OMIM

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: literature only

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.81
CADD	Uncertain	25
DANN	Benign	0.56
PhyloP100		0.89
Mutation Taster		=8/92	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
Splicevardb		3.0
SpliceAI score (max)		0.78		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.78		Position offset: 6

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

Other links and lift over

dbSNP: rs587776839; hg19: chr4-155530122;