X-139530843-G-C

Variant names:

• chrX-139530843-G-C
• rs387906475
• NM_000133.4:c.79G>C

Variant summary

Our verdict is Uncertain significance. The variant received 5 ACMG points: 5P and 0B. PM1 PM2 PP2

The NM_000133.4(F9):​c.79G>C​(p.Glu27Gln) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. 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. E27K) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 23)
• Consequence: F9 NM_000133.4 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 2.35
• Publications: 2 publications found

Genes affected

F9 (HGNC:3551): (coagulation factor IX) This gene encodes vitamin K-dependent coagulation factor IX that circulates in the blood as an inactive zymogen. This factor is converted to an active form by factor XIa, which excises the activation peptide and thus generates a heavy chain and a light chain held together by one or more disulfide bonds. The role of this activated factor IX in the blood coagulation cascade is to activate factor X to its active form through interactions with Ca+2 ions, membrane phospholipids, and factor VIII. Alterations of this gene, including point mutations, insertions and deletions, cause factor IX deficiency, which is a recessive X-linked disorder, also called hemophilia B or Christmas disease. Alternative splicing results in multiple transcript variants encoding different isoforms that may undergo similar proteolytic processing. [provided by RefSeq, Sep 2015]

F9 Gene-Disease associations (from GenCC):

• hemophilia B

  Inheritance: XL Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), ClinGen
• mild hemophilia B

  Inheritance: XL Classification: SUPPORTIVE Submitted by: Orphanet
• moderately severe hemophilia B

  Inheritance: XL Classification: SUPPORTIVE Submitted by: Orphanet
• severe hemophilia B

  Inheritance: XL Classification: SUPPORTIVE Submitted by: Orphanet
• symptomatic form of hemophilia B in female carriers

  Inheritance: XL Classification: SUPPORTIVE Submitted by: Orphanet
• thrombophilia, X-linked, due to factor 9 defect

  Inheritance: XL Classification: LIMITED Submitted by: ClinGen

ACMG classification

Our verdict: Uncertain_significance. The variant received 5 ACMG points.

• PM1: In a hotspot region, there are 5 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 2 uncertain in NM_000133.4
• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 162 curated pathogenic missense variants (we use a threshold of 10). The gene has 21 curated benign missense variants. Gene score misZ: 2.1809 (below the threshold of 3.09). Trascript score misZ: NaN (below the threshold of 3.09). GenCC associations: The gene is linked to hemophilia B, symptomatic form of hemophilia B in female carriers, thrombophilia, X-linked, due to factor 9 defect, mild hemophilia B, severe hemophilia B, moderately severe hemophilia B.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000133.4. 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
	F9	NM_000133.4	MANE Select	c.79G>C	p.Glu27Gln	missense	Exon 1 of 8	NP_000124.1	P00740-1
	F9	NM_001313913.2		c.79G>C	p.Glu27Gln	missense	Exon 1 of 7	NP_001300842.1	P00740-2

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	F9	ENST00000218099.7	TSL:1 MANE Select	c.79G>C	p.Glu27Gln	missense	Exon 1 of 8	ENSP00000218099.2	P00740-1
	F9	ENST00000394090.2	TSL:1	c.79G>C	p.Glu27Gln	missense	Exon 1 of 7	ENSP00000377650.2	P00740-2
	F9	ENST00000479617.2	TSL:5	n.86G>C		non_coding_transcript_exon	Exon 1 of 4

Frequencies

GnomAD3 genomes Cov.: 23

GnomAD4 exome Cov.: 28

GnomAD4 genome Cov.: 23

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.11
BayesDel_addAF	Uncertain	0.061	T
BayesDel_noAF	Benign	-0.15
CADD	Benign	18
DANN	Uncertain	0.99
DEOGEN2	Benign	0.37	T
FATHMM_MKL	Uncertain	0.90	D
LIST_S2	Benign	0.57	T
M_CAP	Uncertain	0.12	D
MetaRNN	Uncertain	0.57	D
MetaSVM	Uncertain	0.60	D
MutationAssessor	Uncertain	2.6	M
PhyloP100		2.4
PrimateAI	Benign	0.39	T
PROVEAN	Benign	-0.74	N
REVEL	Uncertain	0.40
Sift	Benign	0.20	T
Sift4G	Benign	0.45	T
Polyphen		0.035	B
Vest4		0.29
MutPred		0.58		Loss of solvent accessibility (P = 0.0606)
MVP		0.96
MPC		0.35
ClinPred		0.84	D
GERP RS		5.2
PromoterAI		-0.044	Neutral
Varity_R		0.25
gMVP		0.71
Mutation Taster		=29/71	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.020		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: rs387906475; hg19: chrX-138613002;