1-173911981-A-T

Variant names:

• chr1-173911981-A-T
• rs121909569
• NM_000488.4:c.442T>A

Variant summary

Our verdict is Likely pathogenic. The variant received 7 ACMG points: 7P and 0B. PM1 PM2 PM5 PP2

The NM_000488.4(SERPINC1):​c.442T>A​(p.Ser148Thr) variant causes a missense change involving the alteration of a 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. S148P) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 32)
• Consequence: SERPINC1 NM_000488.4 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 8.95
• Publications: 0 publications found

Genes affected

SERPINC1 (HGNC:775): (serpin family C member 1) The protein encoded by this gene, antithrombin III, is a plasma protease inhibitor and a member of the serpin superfamily. This protein inhibits thrombin as well as other activated serine proteases of the coagulation system, and it regulates the blood coagulation cascade. The protein includes two functional domains: the heparin binding-domain at the N-terminus of the mature protein, and the reactive site domain at the C-terminus. The inhibitory activity is enhanced by the presence of heparin. Numerous mutations have been identified for this gene, many of which are known to cause antithrombin-III deficiency which constitutes a strong risk factor for thrombosis. A reduction in the serum level of this protein is associated with severe cases of Coronavirus Disease 19 (COVID-19). [provided by RefSeq, Sep 2020]

SERPINC1 Gene-Disease associations (from GenCC):

• hereditary antithrombin deficiency

  Inheritance: AD, AR, SD Classification: DEFINITIVE, STRONG, SUPPORTIVE, LIMITED Submitted by: Orphanet, Labcorp Genetics (formerly Invitae), Ambry Genetics, Genomics England PanelApp, ClinGen

ACMG classification

Our verdict: Likely_pathogenic. The variant received 7 ACMG points.

• PM1: In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 3 uncertain in NM_000488.4
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr1-173911981-A-G is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 18039.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• PP2: Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 59 curated pathogenic missense variants (we use a threshold of 10). The gene has 8 curated benign missense variants. Gene score misZ: 1.3587 (below the threshold of 3.09). Trascript score misZ: 2.7609 (below the threshold of 3.09). GenCC associations: The gene is linked to hereditary antithrombin deficiency.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SERPINC1	NM_000488.4	c.442T>A	p.Ser148Thr	missense_variant	Exon 3 of 7	ENST00000367698.4	NP_000479.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SERPINC1	ENST00000367698.4	c.442T>A	p.Ser148Thr	missense_variant	Exon 3 of 7	1	NM_000488.4	ENSP00000356671.3
SERPINC1	ENST00000487183.1	n.147T>A		non_coding_transcript_exon_variant	Exon 2 of 4	2
SERPINC1	ENST00000494024.1	n.668T>A		splice_region_variant, non_coding_transcript_exon_variant	Exon 4 of 4	3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.29
BayesDel_addAF	Uncertain	0.096	D
BayesDel_noAF	Benign	-0.10
CADD	Uncertain	25
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.45	.;T
Eigen	Uncertain	0.20
Eigen_PC	Uncertain	0.37
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Benign	0.85	T;T
M_CAP	Benign	0.042	D
MetaRNN	Uncertain	0.61	D;D
MetaSVM	Benign	-0.81	T
MutationAssessor	Benign	1.8	.;L
PhyloP100		8.9
PrimateAI	Uncertain	0.72	T
PROVEAN	Benign	-0.85	.;N
REVEL	Uncertain	0.40
Sift	Benign	0.15	.;T
Sift4G	Benign	0.13	T;T
Polyphen		0.041	.;B
Vest4		0.63
MutPred		0.50		Loss of disorder (P = 0.1225);Loss of disorder (P = 0.1225);
MVP		0.93
MPC		0.95
ClinPred		0.86	D
GERP RS		5.7
Varity_R		0.57
gMVP		0.53
Mutation Taster		=18/82	disease causing

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

Other links and lift over

dbSNP: rs121909569; hg19: chr1-173881119;