rs998009546

Variant names:

• chr2-107992117-G-A
• rs998009546
• NM_021815.5:c.190G>A

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PP3_Strong

The NM_021815.5(SLC5A7):​c.190G>A​(p.Gly64Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000062 in 1,611,856 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 14/22 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Synonymous variant affecting the same amino acid position (i.e. G64G) has been classified as Likely benign.

• Frequency:
  • Genomes: 𝑓 0.000020 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0000048 (0 hom.)
• Consequence: SLC5A7 NM_021815.5 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 9.60
• Publications: 0 publications found

Genes affected

SLC5A7 (HGNC:14025): (solute carrier family 5 member 7) This gene encodes a sodium ion- and chloride ion-dependent high-affinity transporter that mediates choline uptake for acetylcholine synthesis in cholinergic neurons. The protein transports choline from the extracellular space into presynaptic terminals for synthesis into acetylcholine. Increased choline uptake results from increased density of this protein in synaptosomal plasma membranes in response to depolarization of cholinergic terminals. Dysfunction of cholinergic signaling has been implicated in various disorders including depression, attention-deficit disorder, and schizophrenia. An allelic variant of this gene is associated with autosomal dominant distal hereditary motor neuronopathy type VIIA. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jul 2015]

SLC5A7 Gene-Disease associations (from GenCC):

• neuronopathy, distal hereditary motor, type 7A

  Inheritance: AD Classification: STRONG, MODERATE Submitted by: Ambry Genetics, ClinGen, Labcorp Genetics (formerly Invitae)
• congenital myasthenic syndrome 20

  Inheritance: AR Classification: STRONG Submitted by: G2P, Ambry Genetics, PanelApp Australia, Genomics England PanelApp, Labcorp Genetics (formerly Invitae)
• distal hereditary motor neuropathy type 7

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• presynaptic congenital myasthenic syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Uncertain_significance. The variant received 4 ACMG points.

• PP3: MetaRNN computational evidence supports a deleterious effect, 0.98

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SLC5A7	NM_021815.5	c.190G>A	p.Gly64Arg	missense_variant	Exon 3 of 9	ENST00000264047.3	NP_068587.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SLC5A7	ENST00000264047.3	c.190G>A	p.Gly64Arg	missense_variant	Exon 3 of 9	1	NM_021815.5	ENSP00000264047.2
SLC5A7	ENST00000409059.5	c.190G>A	p.Gly64Arg	missense_variant	Exon 3 of 9	1		ENSP00000387346.1

Frequencies

GnomAD3 genomes AF: 0.0000197 AC: 3 AN: 152174 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000241

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: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000294

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.00000398 AC: 1 AN: 251018 AF XY: 0.00

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000290

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000480 AC: 7 AN: 1459682 Hom.: 0 Cov.: 29 AF XY: 0.00000826 AC XY: 6 AN XY: 726294

African (AFR) AF: 0.00 AC: 0 AN: 33438

American (AMR) AF: 0.0000224 AC: 1 AN: 44660

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26084

East Asian (EAS) AF: 0.00 AC: 0 AN: 39650

South Asian (SAS) AF: 0.00 AC: 0 AN: 86114

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53396

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5760

European-Non Finnish (NFE) AF: 0.00000360 AC: 4 AN: 1110278

Other (OTH) AF: 0.0000332 AC: 2 AN: 60302

GnomAD4 genome AF: 0.0000197 AC: 3 AN: 152174 Hom.: 0 Cov.: 32 AF XY: 0.0000135 AC XY: 1 AN XY: 74348

African (AFR) AF: 0.0000241 AC: 1 AN: 41440

American (AMR) AF: 0.00 AC: 0 AN: 15280

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3468

East Asian (EAS) AF: 0.00 AC: 0 AN: 5196

South Asian (SAS) AF: 0.00 AC: 0 AN: 4824

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10620

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 314

European-Non Finnish (NFE) AF: 0.0000294 AC: 2 AN: 68026

Other (OTH) AF: 0.00 AC: 0 AN: 2094

Alfa AF: 0.00 Hom.: 0

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Inborn genetic diseases Uncertain:1

Sep 13, 2016

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Neuronopathy, distal hereditary motor, type 7A;C4310694:Congenital myasthenic syndrome 20 Uncertain:1

Aug 31, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces glycine, which is neutral and non-polar, with arginine, which is basic and polar, at codon 64 of the SLC5A7 protein (p.Gly64Arg). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with SLC5A7-related conditions. ClinVar contains an entry for this variant (Variation ID: 521032). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is expected to disrupt SLC5A7 protein function with a positive predictive value of 80%. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.46	D
BayesDel_noAF	Pathogenic	0.43
CADD	Pathogenic	34
DANN	Pathogenic	1.0
DEOGEN2	Uncertain	0.69	D;D
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	1.1
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.99	.;D
M_CAP	Pathogenic	0.41	D
MetaRNN	Pathogenic	0.98	D;D
MetaSVM	Pathogenic	0.91	D
MutationAssessor	Pathogenic	3.2	M;M
PhyloP100		9.6
PrimateAI	Pathogenic	0.89	D
PROVEAN	Pathogenic	-7.7	D;D
REVEL	Pathogenic	0.85
Sift	Uncertain	0.0010	D;D
Sift4G	Uncertain	0.0020	D;D
Polyphen		1.0	D;D
Vest4		0.96
MutPred		0.89		Gain of methylation at G64 (P = 0.016);Gain of methylation at G64 (P = 0.016);
MVP		0.98
MPC		2.1
ClinPred		1.0	D
GERP RS		6.2
Varity_R		0.97
gMVP		0.99
Mutation Taster		=152/148	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.090		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: rs998009546; hg19: chr2-108608573;