rs1193718145

Positions:

• chr9-128626481-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 4P and 4B. PP2 PP3 PP5_Moderate BS2

The NM_001130438.3(SPTAN1):​c.6370C>T​(p.Arg2124Cys) variant causes a missense change. The variant allele was found at a frequency of 0.00000821 in 1,461,862 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000082 (0 hom.)
• Consequence: SPTAN1 NM_001130438.3 missense
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 3.68

Genes affected

SPTAN1 (HGNC:11273): (spectrin alpha, non-erythrocytic 1) Spectrins are a family of filamentous cytoskeletal proteins that function as essential scaffold proteins that stabilize the plasma membrane and organize intracellular organelles. Spectrins are composed of alpha and beta dimers that associate to form tetramers linked in a head-to-head arrangement. This gene encodes an alpha spectrin that is specifically expressed in nonerythrocytic cells. The encoded protein has been implicated in other cellular functions including DNA repair and cell cycle regulation. Mutations in this gene are the cause of early infantile epileptic encephalopathy-5. Alternate splicing results in multiple transcript variants.[provided by RefSeq, Sep 2010]

ACMG classification

Verdict is Uncertain_significance. Variant got 0 ACMG points.

• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), SPTAN1. . Gene score misZ 5.523 (greater than the threshold 3.09). Trascript score misZ 7.9287 (greater than threshold 3.09). GenCC has associacion of gene with developmental and epileptic encephalopathy, 5, developmental and epileptic encephalopathy, West syndrome.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.771
• PP5: Variant 9-128626481-C-T is Pathogenic according to our data. Variant chr9-128626481-C-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 530418.Status of the report is criteria_provided_single_submitter, 1 stars.
• BS2: High AC in GnomAdExome4 at 12 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
SPTAN1	NM_001130438.3	c.6370C>T	p.Arg2124Cys	missense_variant	49/57	ENST00000372739.7	NP_001123910.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
SPTAN1	ENST00000372739.7	c.6370C>T	p.Arg2124Cys	missense_variant	49/57	1	NM_001130438.3	ENSP00000361824	P3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000821 AC: 12 AN: 1461862 Hom.: 0 Cov.: 37 AF XY: 0.00000963 AC XY: 7 AN XY: 727236

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000108

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Early infantile epileptic encephalopathy with suppression bursts Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Sep 27, 2022

In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be disruptive. ClinVar contains an entry for this variant (Variation ID: 530418). This missense change has been observed in individual(s) with clinical features of developmental and epileptic encephalopathy (PMID: 31452935; Invitae). In at least one individual the variant was observed to be de novo. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces arginine, which is basic and polar, with cysteine, which is neutral and slightly polar, at codon 2124 of the SPTAN1 protein (p.Arg2124Cys). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.34	D
BayesDel_noAF	Pathogenic	0.25
CADD	Pathogenic	28
DANN	Pathogenic	1.0
DEOGEN2	Uncertain	0.44	T;.;.;.;.
Eigen	Pathogenic	0.78
Eigen_PC	Pathogenic	0.74
FATHMM_MKL	Uncertain	0.90	D
LIST_S2	Pathogenic	0.99	D;D;D;D;D
M_CAP	Uncertain	0.12	D
MetaRNN	Pathogenic	0.77	D;D;D;D;D
MetaSVM	Uncertain	0.12	D
MutationAssessor	Pathogenic	2.9	M;.;.;.;.
MutationTaster	Benign	1.0	D;D;D
PrimateAI	Pathogenic	0.90	D
PROVEAN	Pathogenic	-6.2	D;.;D;.;.
REVEL	Uncertain	0.53
Sift	Uncertain	0.0010	D;.;D;.;.
Sift4G	Pathogenic	0.0010	D;D;D;D;D
Polyphen		1.0	D;.;D;D;.
Vest4		0.77
MutPred		0.54		Loss of phosphorylation at S2122 (P = 0.0541);.;.;.;.;
MVP		0.82
MPC		2.1
ClinPred		1.0	D
GERP RS		5.7
Varity_R		0.57
gMVP		0.66

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: rs1193718145; hg19: chr9-131388760;