rs137852391

Variant names:

• chrX-154993127-G-A
• rs137852391
• NM_000132.4:c.410C>T

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PM2 PM5 PP3_Strong

The NM_000132.4(F8):​c.410C>T​(p.Thr137Ile) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic 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. T137A) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 23)
• Consequence: F8 NM_000132.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter P:1 U:1
• Conservation: PhyloP100: 4.04

Genes affected

F8 (HGNC:3546): (coagulation factor VIII) This gene encodes coagulation factor VIII, which participates in the intrinsic pathway of blood coagulation; factor VIII is a cofactor for factor IXa which, in the presence of Ca+2 and phospholipids, converts factor X to the activated form Xa. This gene produces two alternatively spliced transcripts. Transcript variant 1 encodes a large glycoprotein, isoform a, which circulates in plasma and associates with von Willebrand factor in a noncovalent complex. This protein undergoes multiple cleavage events. Transcript variant 2 encodes a putative small protein, isoform b, which consists primarily of the phospholipid binding domain of factor VIIIc. This binding domain is essential for coagulant activity. Defects in this gene results in hemophilia A, a common recessive X-linked coagulation disorder. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Likely_pathogenic. Variant got 8 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chrnull-null-null-null is described in UniProt as null.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.968

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
F8	NM_000132.4	c.410C>T	p.Thr137Ile	missense_variant	Exon 4 of 26	ENST00000360256.9	NP_000123.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
F8	ENST00000360256.9	c.410C>T	p.Thr137Ile	missense_variant	Exon 4 of 26	1	NM_000132.4	ENSP00000353393.4

Frequencies

GnomAD3 genomes Cov.: 23

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 23

ClinVar

Significance: Uncertain significance

Submissions summary: Pathogenic:1 Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Hereditary factor VIII deficiency disease Pathogenic:1

Jan 01, 1995

OMIM

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: literature only

- -

not specified Uncertain:1

Oct 11, 2024

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Variant summary: F8 c.410C>T (p.Thr137Ile) results in a non-conservative amino acid change located in the Multicopper oxidase-like, N-terminal domian (IPR011707) of the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant was absent in 182499 control chromosomes. c.410C>T has been reported in the literature in two related individuals affected with Factor VIII Deficiency (Hemophilia A) (Schwaab_1995). These data indicate that the variant may be associated with disease. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. The following publications have been ascertained in the context of this evaluation (PMID: 8547094). ClinVar contains an entry for this variant (Variation ID: 10174). Based on the evidence outlined above, the variant was classified as VUS-possibly pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.68
BayesDel_addAF	Pathogenic	0.66	D
BayesDel_noAF	Pathogenic	0.70
CADD	Benign	20
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.99	D;D;D
FATHMM_MKL	Uncertain	0.94	D
LIST_S2	Uncertain	0.89	D;D;D
M_CAP	Pathogenic	0.81	D
MetaRNN	Pathogenic	0.97	D;D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Uncertain	2.6	M;.;.
PrimateAI	Benign	0.48	T
PROVEAN	Pathogenic	-5.5	D;D;D
REVEL	Pathogenic	0.95
Sift	Pathogenic	0.0	D;D;D
Sift4G	Uncertain	0.0020	D;.;.
Polyphen		1.0	D;D;.
Vest4		0.86
MutPred		0.82		Loss of phosphorylation at T137 (P = 0.0312);.;.;
MVP		1.0
MPC		1.7
ClinPred		1.0	D
GERP RS		4.5
Varity_R		0.95
gMVP		0.99

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.13		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: rs137852391; hg19: chrX-154221402;