rs267607061

Positions:

Variant summary

Our verdict is Pathogenic. Variant got 19 ACMG points: 19P and 0B. PM1PM2PM5PP2PP3_StrongPP5_Very_Strong

The ENST00000426263.10(SLC2A1):c.277C>T(p.Arg93Trp) variant causes a missense, splice region change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000125 in 1,600,800 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 2/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R93Q) has been classified as Likely pathogenic.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)

Exomes 𝑓: 6.9e-7 ( 0 hom. )

Consequence

SLC2A1
ENST00000426263.10 missense, splice_region

Scores

Splicing: ADA: 0.9721

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:9

Conservation

PhyloP100: 2.92

Variant links:

Genes affected

SLC2A1 (HGNC:11005): (solute carrier family 2 member 1) This gene encodes a major glucose transporter in the mammalian blood-brain barrier. The encoded protein is found primarily in the cell membrane and on the cell surface, where it can also function as a receptor for human T-cell leukemia virus (HTLV) I and II. Mutations in this gene have been found in a family with paroxysmal exertion-induced dyskinesia. [provided by RefSeq, Apr 2013]

SLC2A1 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 19 ACMG points.

PM1

In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 8 uncertain in ENST00000426263.10

PM2

Very rare variant in population databases, with high coverage;

PM5

Other missense variant is known to change same aminoacid residue: Variant chr1-42930864-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 623684.We mark this variant Likely_pathogenic, oryginal submissions are: {Likely_pathogenic=1, Pathogenic=1, Uncertain_significance=2}.

PP2

Missense variant in gene, where missense usually causes diseases (based on misZ statistic), SLC2A1. . Gene score misZ 2.9256 (greater than the threshold 3.09). Trascript score misZ 4.6729 (greater than threshold 3.09). GenCC has associacion of gene with childhood absence epilepsy, dystonia 9, epilepsy, idiopathic generalized, susceptibility to, 12, GLUT1 deficiency syndrome, myoclonic-astatic epilepsy, childhood onset GLUT1 deficiency syndrome 2, hereditary cryohydrocytosis with reduced stomatin, encephalopathy due to GLUT1 deficiency.

PP3

MetaRNN computational evidence supports a deleterious effect, 0.944

PP5

Variant 1-42930865-G-A is Pathogenic according to our data. Variant chr1-42930865-G-A is described in ClinVar as [Pathogenic]. Clinvar id is 16117.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr1-42930865-G-A is described in Lovd as [Likely_pathogenic]. Variant chr1-42930865-G-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
SLC2A1	NM_006516.4 linkuse as main transcript	c.277C>T	p.Arg93Trp	missense_variant, splice_region_variant	4/10	ENST00000426263.10	NP_006507.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
SLC2A1	ENST00000426263.10 linkuse as main transcript	c.277C>T	p.Arg93Trp	missense_variant, splice_region_variant	4/10	1	NM_006516.4	ENSP00000416293	P1

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152118

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

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:

0.0000943

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.00

Gnomad OTH

AF:

0.00

GnomAD4 exome

AF:

6.90e-7

AC:

AN:

1448682

Hom.:

Cov.:

AF XY:

0.00000139

AC XY:

AN XY:

721034

show subpopulations

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:

8.99e-7

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.00000657

AC:

AN:

152118

Hom.:

Cov.:

AF XY:

0.0000135

AC XY:

AN XY:

74298

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.0000943

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:9

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not provided

Pathogenic:3

Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Aug 24, 2018	The R93W variant in the SLC2A1 gene has been reported previously in multiple unrelated individuals with glucose transporter type 1 deficiency syndrome (Glut1-DS) (Rotstein et al., 2009; Leen et al., 2010). The R93W variant is not observed in large population cohorts (Lek et al., 2016). The R93W variant is a non-conservative amino acid substitution, which is likely to impact secondary protein structure as these residues differ in polarity, charge, size and/or other properties. Functional studies suggest that the R93W variant results in reduced glucose uptake (Pascual et al., 2008). We interpret R93W as a pathogenic variant. -
Pathogenic, no assertion criteria provided	clinical testing	Diagnostic Laboratory, Department of Genetics, University Medical Center Groningen	-	- -
Likely pathogenic, no assertion criteria provided	clinical testing	Joint Genome Diagnostic Labs from Nijmegen and Maastricht, Radboudumc and MUMC+	-	- -

Encephalopathy due to GLUT1 deficiency

Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	New York Genome Center	Sep 10, 2019	The variant c.277C>T, p.Arg93Trp has been reported in multiple individuals with GLUT1 deficiency syndrome [MIM#606777] [PMID: 24847886; PMID: 2344855; PMID:23106342; PMID: 19996082]. This mutation is located in the first cytosolic loop of the protein [PMID: 19996082]. The variant has 0.003% allele frequency in the gnomAD database (1 out of 31,368 heterozygous alleles) indicating this is a rare variant and in silico tool predicts the variant is expected to be deleterious. Functional studies suggest that the variant results in reduced glucose uptake [PMID: 18387950]. Based on the available evidence, the variant c.277C>T, p.Arg93Trp in the SLC2A1 gene is classified as pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	Genome-Nilou Lab	Apr 11, 2023	- -

SLC2A1-related disorder

Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

PreventionGenetics, part of Exact Sciences

Aug 18, 2022

The SLC2A1 c.277C>T variant is predicted to result in the amino acid substitution p.Arg93Trp. This variant has been reported in multiple individuals with GLUT1 deficiency (Joshi et al. 2008. PubMed ID: 18403583; Arsov et al. 2012. PubMed ID: 23106342; Ramm-Pettersen et al. 2013. PubMed ID: 23448551; Supplemental Table for Symonds et al. 2019. PubMed ID: 31302675) and an individual with alternating hemiplegia of childhood (Rotstein et al, 2009. PubMed ID: 19996082). An alternate substitution of the same amino acid has also been reported in association with GLUT1 deficiency (Magrinelli et al. 2020. PubMed ID: 32753446). In a functional study, the p.Arg93Trp substitution was reported to reduce glucose transport in erythrocytes (Pascual et al. 2008. PubMed ID: 18387950) This variant is reported in 0.029% of alleles in individuals of European (Finnish) descent in gnomAD (1 of 31,368 total alleles in http://gnomad.broadinstitute.org/variant/1-43396536-G-A). This variant is interpreted as pathogenic or likely pathogenic by multiple independent submitters to ClinVar (https://www.ncbi.nlm.nih.gov/clinvar/variation/16117). Based on the collective evidence, this variant is interpreted as pathogenic. -

Childhood onset GLUT1 deficiency syndrome 2

Pathogenic:1

Pathogenic, no assertion criteria provided

literature only

OMIM

Dec 08, 2009

- -

GLUT1 deficiency syndrome 1, autosomal recessive

Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jan 12, 2022

Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). For these reasons, this variant has been classified as Pathogenic. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may create or strengthen a splice site. ClinVar contains an entry for this variant (Variation ID: 16117). This missense change has been observed in individual(s) with low cerebral spinal fluid blood glucose concentrations, findings that are highly specific for GLUT1 deficiency syndrome (PMID: 18403583, 19996082, 20129935, 23106342, 23448551). In at least one individual the variant was observed to be de novo. It has also been observed to segregate with disease in related individuals. The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. This sequence change replaces arginine, which is basic and polar, with tryptophan, which is neutral and slightly polar, at codon 93 of the SLC2A1 protein (p.Arg93Trp). -

Seizure

Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Génétique des Maladies du Développement, Hospices Civils de Lyon

Aug 03, 2021

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.78

BayesDel_addAF

Pathogenic

0.39

BayesDel_noAF

Pathogenic

0.32

CADD

Pathogenic

DANN

Pathogenic

1.0

DEOGEN2

Pathogenic

0.93

D;.

Eigen

Uncertain

0.64

Eigen_PC

Uncertain

0.53

FATHMM_MKL

Uncertain

0.91

LIST_S2

Pathogenic

0.99

D;D

M_CAP

Uncertain

0.22

MetaRNN

Pathogenic

0.94

D;D

MetaSVM

Uncertain

0.64

MutationAssessor

Pathogenic

3.8

H;.

MutationTaster

Benign

1.0

D;D

PrimateAI

Pathogenic

0.82

PROVEAN

Pathogenic

-5.2

D;.

REVEL

Pathogenic

0.74

Sift

Uncertain

0.0060

D;.

Sift4G

Uncertain

0.0050

D;D

Polyphen

1.0

D;.

Vest4

0.96

MutPred

0.75

Gain of catalytic residue at M96 (P = 0.0048);.;

MVP

0.95

MPC

2.1

ClinPred

1.0

GERP RS

5.4

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.1

Varity_R

0.86

gMVP

0.87

Splicing

Name

Calibrated prediction

Score

Prediction

dbscSNV1_ADA

Pathogenic

0.97

dbscSNV1_RF

Benign

0.68

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over