rs281875172

Positions:

• chr11-57606019-T-A

Variant summary

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

The NM_000062.3(SERPING1):​c.695T>A​(p.Ile232Lys) 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. I232R) has been classified as Pathogenic.

• Frequency: Genomes: not found (cov: 32)
• Consequence: SERPING1 NM_000062.3 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2 O:1
• Conservation: PhyloP100: 4.39

Genes affected

SERPING1 (HGNC:1228): (serpin family G member 1) This gene encodes a highly glycosylated plasma protein involved in the regulation of the complement cascade. Its encoded protein, C1 inhibitor, inhibits activated C1r and C1s of the first complement component and thus regulates complement activation. It is synthesized in the liver, and its deficiency is associated with hereditary angioneurotic oedema (HANE). Alternative splicing results in multiple transcript variants encoding the same isoform. [provided by RefSeq, May 2020]

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 chr11-57606019-T-G is described in Lovd as [Pathogenic].
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.98

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
SERPING1	NM_000062.3	c.695T>A	p.Ile232Lys	missense_variant	5/8	ENST00000278407.9	NP_000053.2
SERPING1	NM_001032295.2	c.695T>A	p.Ile232Lys	missense_variant	4/7		NP_001027466.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
SERPING1	ENST00000278407.9	c.695T>A	p.Ile232Lys	missense_variant	5/8	1	NM_000062.3	ENSP00000278407	P2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2 Other:1

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Uncertain:1 Other:1

Uncertain significance, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Oct 04, 2023	This sequence change replaces isoleucine, which is neutral and non-polar, with lysine, which is basic and polar, at codon 232 of the SERPING1 protein (p.Ile232Lys). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individuals with hereditary angioedema (PMID: 22994404; Invitae). ClinVar contains an entry for this variant (Variation ID: 68255). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt SERPING1 protein function. This variant disrupts the p.Ile232 amino acid residue in SERPING1. Other variant(s) that disrupt this residue have been observed in individuals with SERPING1-related conditions (PMID: 26154504), which suggests that this may be a clinically significant amino acid residue. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -
not provided, no classification provided	literature only	UniProtKB/Swiss-Prot	-	- -

Inborn genetic diseases Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Mar 09, 2015

The p.I232K variant (also known as c.695T>A), located in coding exon 4 of the SERPING1 gene, results from a T to A substitution at nucleotide position 695. The isoleucine at codon 232 is replaced by lysine, an amino acid with dissimilar properties. This variant was detected in one patient with a diagnosis of hereditay angioedema, but absent in 53 healthy control individuals (Xu YY, Allergy 2012; 67(11):1430-6). This variant was previously reported in the SNPDatabase as rs281875172. This amino acid position is not well conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Since clinical data on this variant is limited at this time, its clinical significance is unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.90
BayesDel_addAF	Pathogenic	0.38	D
BayesDel_noAF	Pathogenic	0.31
CADD	Uncertain	24
DANN	Benign	0.97
DEOGEN2	Pathogenic	0.81	D;.;.;.;D
Eigen	Uncertain	0.50
Eigen_PC	Uncertain	0.41
FATHMM_MKL	Benign	0.68	D
LIST_S2	Benign	0.73	T;T;T;T;T
M_CAP	Pathogenic	0.58	D
MetaRNN	Pathogenic	0.98	D;D;D;D;D
MetaSVM	Uncertain	0.61	D
MutationAssessor	Pathogenic	2.9	M;.;.;.;.
MutationTaster	Benign	0.98	D;D;D;D;D
PrimateAI	Benign	0.48	T
PROVEAN	Pathogenic	-4.7	D;D;D;D;D
REVEL	Pathogenic	0.76
Sift	Uncertain	0.0020	D;D;D;D;D
Sift4G	Uncertain	0.024	D;D;D;D;D
Polyphen		0.99	D;.;.;.;P
Vest4		0.86
MutPred		0.88		.;.;.;.;Gain of disorder (P = 0.0065);
MVP		0.99
MPC		1.3
ClinPred		0.99	D
GERP RS		5.2
Varity_R		0.90
gMVP		0.90

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: rs281875172; hg19: chr11-57373492;