rs796053315

Variant names:

• chr9-128582527-A-G
• rs796053315
• NM_001130438.3:c.1621A>G

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM2 BP4 BP6

The NM_001130438.3(SPTAN1):​c.1621A>G​(p.Met541Val) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,804 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: SPTAN1 NM_001130438.3 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:2 B:1
• Conservation: PhyloP100: 8.95
• Publications: 0 publications found

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]

SPTAN1 Gene-Disease associations (from GenCC):

• developmental and epileptic encephalopathy, 5

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: G2P, Ambry Genetics, Labcorp Genetics (formerly Invitae), Laboratory for Molecular Medicine
• genetic developmental and epileptic encephalopathy

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• infantile spasms

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

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=0.2845812).
• BP6: Variant 9-128582527-A-G is Benign according to our data. Variant chr9-128582527-A-G is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 207321.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SPTAN1	NM_001130438.3	c.1621A>G	p.Met541Val	missense_variant	Exon 13 of 57	ENST00000372739.7	NP_001123910.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SPTAN1	ENST00000372739.7	c.1621A>G	p.Met541Val	missense_variant	Exon 13 of 57	1	NM_001130438.3	ENSP00000361824.4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461804 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 727214

African (AFR) AF: 0.00 AC: 0 AN: 33480

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

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53332

Middle Eastern (MID) AF: 0.000173 AC: 1 AN: 5768

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1112010

Other (OTH) AF: 0.0000166 AC: 1 AN: 60396

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:2 Benign:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Developmental and epileptic encephalopathy Uncertain:1

Nov 30, 2016

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

In summary, this variant is a rare missense change that is not predicted to affect protein function. There is no indication that it causes disease, but the available evidence is currently insufficient to prove that conclusively. Therefore, it has been classified as a Variant of Uncertain Significance. 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 tolerated, but these predictions have not been confirmed by published functional studies. This variant is not present in population databases (ExAC no frequency) and has not been reported in the literature in individuals with a SPTAN1-related disease. ClinVar contains an entry for this variant (Variation ID: 207321). This sequence change replaces methionine with valine at codon 541 of the SPTAN1 protein (p.Met541Val). The methionine residue is moderately conserved and there is a small physicochemical difference between methionine and valine. -

Developmental and epileptic encephalopathy, 5 Uncertain:1

Jul 15, 2021

Genome-Nilou Lab

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

not provided Benign:1

Sep 11, 2018

GeneDx

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.083
BayesDel_addAF	Benign	-0.061	T
BayesDel_noAF	Benign	-0.33
CADD	Uncertain	24
DANN	Uncertain	0.98
DEOGEN2	Benign	0.11	T;.;.;.;.
Eigen	Benign	-0.10
Eigen_PC	Benign	0.17
FATHMM_MKL	Pathogenic	1.0	D
LIST_S2	Pathogenic	0.98	D;D;D;D;D
M_CAP	Benign	0.0034	T
MetaRNN	Benign	0.28	T;T;T;T;T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	0.0	N;.;N;N;.
PhyloP100		8.9
PrimateAI	Uncertain	0.56	T
PROVEAN	Benign	-0.67	N;.;N;N;.
REVEL	Benign	0.19
Sift	Benign	0.036	D;.;D;D;.
Sift4G	Uncertain	0.027	D;D;D;D;D
Polyphen		0.0080	B;.;B;B;.
Vest4		0.52
MutPred		0.61		Loss of disorder (P = 0.0957);Loss of disorder (P = 0.0957);Loss of disorder (P = 0.0957);Loss of disorder (P = 0.0957);Loss of disorder (P = 0.0957);
MVP		0.53
MPC		0.79
ClinPred		0.68	D
GERP RS		6.0
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.26
gMVP		0.24
Mutation Taster		=90/10	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: rs796053315; hg19: chr9-131344806;