3-167794797-A-G

Variant names:

• chr3-167794797-A-G
• rs772141992
• NM_001122752.2:c.854A>G

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_001122752.2(SERPINI1):​c.854A>G​(p.Lys285Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,158 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/22 in silico tools predict a benign 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. K285Q) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: SERPINI1 NM_001122752.2 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 3.27
• Publications: 0 publications found

Genes affected

SERPINI1 (HGNC:8943): (serpin family I member 1) This gene encodes a member of the serpin superfamily of serine proteinase inhibitors. The protein is primarily secreted by axons in the brain, and preferentially reacts with and inhibits tissue-type plasminogen activator. It is thought to play a role in the regulation of axonal growth and the development of synaptic plasticity. Mutations in this gene result in familial encephalopathy with neuroserpin inclusion bodies (FENIB), which is a dominantly inherited form of familial encephalopathy and epilepsy characterized by the accumulation of mutant neuroserpin polymers. Multiple alternatively spliced variants, encoding the same protein, have been identified. [provided by RefSeq, Jul 2008]

SERPINI1 Gene-Disease associations (from GenCC):

• progressive myoclonus epilepsy

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• familial encephalopathy with neuroserpin inclusion bodies

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

ENSG00000287319 (HGNC:):

ACMG classification

Our verdict: Uncertain_significance. The variant received 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.12357351).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001122752.2. 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
	SERPINI1	NM_001122752.2	MANE Select	c.854A>G	p.Lys285Arg	missense	Exon 5 of 9	NP_001116224.1
	SERPINI1	NM_005025.5		c.854A>G	p.Lys285Arg	missense	Exon 5 of 9	NP_005016.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SERPINI1	ENST00000446050.7	TSL:1 MANE Select	c.854A>G	p.Lys285Arg	missense	Exon 5 of 9	ENSP00000397373.2
	SERPINI1	ENST00000295777.9	TSL:1	c.854A>G	p.Lys285Arg	missense	Exon 5 of 9	ENSP00000295777.5
	SERPINI1	ENST00000472747.2	TSL:3	c.*118A>G		downstream_gene	N/A	ENSP00000420561.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461158 Hom.: 0 Cov.: 32 AF XY: 0.00000138 AC XY: 1 AN XY: 726874

African (AFR) AF: 0.00 AC: 0 AN: 33444

American (AMR) AF: 0.00 AC: 0 AN: 44592

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26120

East Asian (EAS) AF: 0.00 AC: 0 AN: 39694

South Asian (SAS) AF: 0.00 AC: 0 AN: 86238

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53408

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5560

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1111748

Other (OTH) AF: 0.00 AC: 0 AN: 60354

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Familial encephalopathy with neuroserpin inclusion bodies Uncertain:1

Nov 14, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces lysine, which is basic and polar, with arginine, which is basic and polar, at codon 285 of the SERPINI1 protein (p.Lys285Arg). This variant is present in population databases (no rsID available, gnomAD 0.007%). This variant has not been reported in the literature in individuals affected with SERPINI1-related conditions. ClinVar contains an entry for this variant (Variation ID: 1397005). 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 not expected to disrupt SERPINI1 protein function with a negative predictive value of 80%. 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.

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.11
BayesDel_addAF	Benign	-0.13	T
BayesDel_noAF	Benign	-0.43
CADD	Benign	19
DANN	Uncertain	0.99
DEOGEN2	Benign	0.17	T
Eigen	Benign	-0.39
Eigen_PC	Benign	-0.23
FATHMM_MKL	Uncertain	0.84	D
LIST_S2	Benign	0.79	T
M_CAP	Benign	0.025	T
MetaRNN	Benign	0.12	T
MetaSVM	Benign	-0.55	T
MutationAssessor	Benign	0.67	N
PhyloP100		3.3
PrimateAI	Uncertain	0.57	T
PROVEAN	Benign	-0.65	N
REVEL	Benign	0.25
Sift	Benign	0.47	T
Sift4G	Benign	0.49	T
Polyphen		0.0050	B
Vest4		0.19
MutPred		0.46		Loss of ubiquitination at K285 (P = 0.0446)
MVP		0.30
MPC		0.077
ClinPred		0.58	D
GERP RS		4.4
Varity_R		0.31
gMVP		0.18
Mutation Taster		=87/13	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs772141992; hg19: chr3-167512585;