1-42943239-T-C

Position:

• chr1-42943239-T-C

Variant summary

Our verdict is Pathogenic. Variant got 19 ACMG points: 19P and 0B. PM1 PM2 PM5 PP2 PP3_Strong PP5_Very_Strong

The NM_006516.4(SLC2A1):​c.101A>G​(p.Asn34Ser) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. N34I) has been classified as Pathogenic.

• Frequency: Genomes: not found (cov: 32)
• Consequence: SLC2A1 NM_006516.4 missense
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:7
• Conservation: PhyloP100: 6.66

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]

ACMG classification

Verdict is Pathogenic. Variant got 19 ACMG points.

• PM1: In a strand (size 2) in uniprot entity GTR1_HUMAN there are 6 pathogenic changes around while only 0 benign (100%) in NM_006516.4
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr1-42943240-T-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 159921.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• 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, 0.985
• PP5: Variant 1-42943239-T-C is Pathogenic according to our data. Variant chr1-42943239-T-C is described in ClinVar as [Pathogenic]. Clinvar id is 662199.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr1-42943239-T-C is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
SLC2A1	NM_006516.4	c.101A>G	p.Asn34Ser	missense_variant	2/10	ENST00000426263.10

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SLC2A1	ENST00000426263.10	c.101A>G	p.Asn34Ser	missense_variant	2/10	1	NM_006516.4	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 29

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:7

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Encephalopathy due to GLUT1 deficiency Pathogenic:3

Pathogenic, criteria provided, single submitter	clinical testing	Institute of Human Genetics, University of Leipzig Medical Center	Oct 06, 2020	This variant was identified as de novo (maternity and paternity confirmed). -
Pathogenic, criteria provided, single submitter	clinical testing	Institute of Human Genetics Munich, Klinikum Rechts Der Isar, TU München	Oct 07, 2019	- -
Pathogenic, criteria provided, single submitter	clinical testing	Genome-Nilou Lab	Apr 11, 2023	- -

not provided Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Institute of Medical Genetics and Applied Genomics, University Hospital Tübingen	Oct 23, 2020	- -
Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Jan 06, 2022	Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 15622525, 30616884, 28961260, 29199027, 16217704, 28018440, 30895386, 28116237, 23340081, 32025761, 32712428, 24847886) -

GLUT1 deficiency syndrome 1, autosomal recessive Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Oct 05, 2022

This variant is not present in population databases (gnomAD no frequency). This sequence change replaces asparagine, which is neutral and polar, with serine, which is neutral and polar, at codon 34 of the SLC2A1 protein (p.Asn34Ser). This missense change has been observed in individual(s) with autosomal dominant GLUT1 deficiency (PMID: 15622525, 16217704, 23340081, 28116237, 28961260). In at least one individual the variant was observed to be de novo. For these reasons, this variant has been classified as 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: 662199). This variant is also known as c.280A>G. -

Dystonia 9;C1837206:Hereditary cryohydrocytosis with reduced stomatin;C1842534:Childhood onset GLUT1 deficiency syndrome 2;C3553859:Epilepsy, idiopathic generalized, susceptibility to, 12;C4551966:Encephalopathy due to GLUT1 deficiency Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Fulgent Genetics, Fulgent Genetics

Jan 27, 2022

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.53
BayesDel_addAF	Benign	-0.031	T
BayesDel_noAF	Benign	-0.28
CADD	Pathogenic	28
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.84	D
Eigen	Uncertain	0.66
Eigen_PC	Uncertain	0.66
FATHMM_MKL	Uncertain	0.93	D
LIST_S2	Uncertain	0.92	D
M_CAP	Uncertain	0.22	D
MetaRNN	Pathogenic	0.99	D
MetaSVM	Uncertain	-0.051	T
MutationAssessor	Benign	1.7	L
MutationTaster	Benign	1.0	D;D
PrimateAI	Uncertain	0.53	T
PROVEAN	Uncertain	-4.0	D
REVEL	Uncertain	0.59
Sift	Benign	0.033	D
Sift4G	Uncertain	0.033	D
Polyphen		0.99	D
Vest4		0.90
MutPred		0.93		Loss of ubiquitination at K38 (P = 0.0618);
MVP		0.84
MPC		1.8
ClinPred		0.99	D
GERP RS		5.2
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.85
gMVP		0.96

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: rs80359812; hg19: chr1-43408910;