3-167790418-T-C

Variant names:

• chr3-167790418-T-C
• rs61761891
• NM_001122752.2:c.297T>C

Variant summary

Our verdict is Likely benign. The variant received -5 ACMG points: 2P and 7B. PM2 BP4_Strong BP6_Moderate BP7

The NM_005025.5(SERPINI1):​c.297T>C​(p.Ala99Ala) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,626 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 (★). Synonymous variant affecting the same amino acid position (i.e. A99A) has been classified as Benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: SERPINI1 NM_005025.5 synonymous
• Clinical Significance: Likely benign criteria provided, single submitter B:1
• Conservation: PhyloP100: -0.451
• 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: Likely_benign. The variant received -5 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.84).
• BP6: Variant 3-167790418-T-C is Benign according to our data. Variant chr3-167790418-T-C is described in ClinVar as Likely_benign. ClinVar VariationId is 1155118.Status of the report is criteria_provided_single_submitter, 1 stars.
• BP7: Synonymous conserved (PhyloP=-0.451 with no splicing effect.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_005025.5. 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.297T>C	p.Ala99Ala	synonymous	Exon 3 of 9	NP_001116224.1
	SERPINI1	NM_005025.5		c.297T>C	p.Ala99Ala	synonymous	Exon 3 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.297T>C	p.Ala99Ala	synonymous	Exon 3 of 9	ENSP00000397373.2
	SERPINI1	ENST00000295777.9	TSL:1	c.297T>C	p.Ala99Ala	synonymous	Exon 3 of 9	ENSP00000295777.5
	SERPINI1	ENST00000872947.1		c.297T>C	p.Ala99Ala	synonymous	Exon 3 of 9	ENSP00000543006.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461626 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 727118

African (AFR) AF: 0.00 AC: 0 AN: 33472

American (AMR) AF: 0.00 AC: 0 AN: 44718

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26128

East Asian (EAS) AF: 0.00 AC: 0 AN: 39664

South Asian (SAS) AF: 0.00 AC: 0 AN: 86248

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53418

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5762

European-Non Finnish (NFE) AF: 0.00000180 AC: 2 AN: 1111828

Other (OTH) AF: 0.00 AC: 0 AN: 60388

GnomAD4 genome Cov.: 32

ClinVar

ClinVar submissions as Germline

Significance: Likely benign

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
-	-	1	Familial encephalopathy with neuroserpin inclusion bodies (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.84
CADD	Benign	1.3
DANN	Benign	0.42
PhyloP100		-0.45

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: rs61761891; hg19: chr3-167508206;