3-167789156-C-T

Variant names:

• chr3-167789156-C-T
• rs1182632779
• NM_001122752.2:c.28C>T

Variant summary

Our verdict is Benign. The variant received -9 ACMG points: 0P and 9B. BP4_Moderate BP6_Moderate BP7 BS2

The NM_001122752.2(SERPINI1):​c.28C>T​(p.Leu10Leu) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000062 in 1,613,922 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★).

• Frequency:
  • Genomes: 𝑓 0.000053 (0 hom., cov: 33)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: SERPINI1 NM_001122752.2 synonymous
• Clinical Significance: Likely benign criteria provided, single submitter B:1
• Conservation: PhyloP100: 2.37
• 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)

ACMG classification

Our verdict: Benign. The variant received -9 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.45).
• BP6: Variant 3-167789156-C-T is Benign according to our data. Variant chr3-167789156-C-T is described in ClinVar as [Likely_benign]. Clinvar id is 2903691.Status of the report is criteria_provided_single_submitter, 1 stars.
• BP7: Synonymous conserved (PhyloP=2.37 with no splicing effect.
• BS2: High AC in GnomAd4 at 8 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SERPINI1	NM_001122752.2	c.28C>T	p.Leu10Leu	synonymous_variant	Exon 2 of 9	ENST00000446050.7	NP_001116224.1
SERPINI1	NM_005025.5	c.28C>T	p.Leu10Leu	synonymous_variant	Exon 2 of 9		NP_005016.1
SERPINI1	XM_017006618.3	c.28C>T	p.Leu10Leu	synonymous_variant	Exon 2 of 9		XP_016862107.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SERPINI1	ENST00000446050.7	c.28C>T	p.Leu10Leu	synonymous_variant	Exon 2 of 9	1	NM_001122752.2	ENSP00000397373.2
SERPINI1	ENST00000295777.9	c.28C>T	p.Leu10Leu	synonymous_variant	Exon 2 of 9	1		ENSP00000295777.5
SERPINI1	ENST00000472747.2	c.28C>T	p.Leu10Leu	synonymous_variant	Exon 2 of 5	3		ENSP00000420561.2
SERPINI1	ENST00000472941.5	c.28C>T	p.Leu10Leu	synonymous_variant	Exon 2 of 3	3		ENSP00000420133.1

Frequencies

GnomAD3 genomes AF: 0.0000526 AC: 8 AN: 152164 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.000193

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461758 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 727180

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.0000299 AC: 1 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26132

East Asian (EAS) AF: 0.00 AC: 0 AN: 39692

South Asian (SAS) AF: 0.00 AC: 0 AN: 86254

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53360

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5760

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1111962

Other (OTH) AF: 0.00 AC: 0 AN: 60394

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.000000), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome AF: 0.0000526 AC: 8 AN: 152164 Hom.: 0 Cov.: 33 AF XY: 0.0000807 AC XY: 6 AN XY: 74350

African (AFR) AF: 0.000193 AC: 8 AN: 41420

American (AMR) AF: 0.00 AC: 0 AN: 15282

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3470

East Asian (EAS) AF: 0.00 AC: 0 AN: 5206

South Asian (SAS) AF: 0.00 AC: 0 AN: 4838

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10606

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 68022

Other (OTH) AF: 0.00 AC: 0 AN: 2092

Alfa AF: 0.0000661 Hom.: 0

Bravo AF: 0.0000264

ClinVar

Significance: Likely benign

Submissions summary: Benign:1

Revision: criteria provided, single submitter

Submissions by phenotype

Familial encephalopathy with neuroserpin inclusion bodies Benign:1

Jan 27, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.45
CADD	Benign	5.9
DANN	Benign	0.42
PhyloP100		2.4

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.030		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: rs1182632779; hg19: chr3-167506944;