rs376187918

Positions:

• chr2-227699325-C-A
• chr2-227699325-C-T

Variant summary

Our verdict is Benign. Variant got -8 ACMG points: 0P and 8B. BP4_Moderate BP6 BP7 BS2

The NM_025243.4(SLC19A3):​c.390G>T​(p.Val130=) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000341 in 1,614,020 control chromosomes in the GnomAD database, including 2 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. V130V) has been classified as Likely benign.

• Frequency:
  • Genomes: 𝑓 0.00017 (0 hom., cov: 32)
  • Exomes 𝑓: 0.00036 (2 hom.)
• Consequence: SLC19A3 NM_025243.4 synonymous
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1 B:3
• Conservation: PhyloP100: -0.226

Genes affected

SLC19A3 (HGNC:16266): (solute carrier family 19 member 3) This gene encodes a ubiquitously expressed transmembrane thiamine transporter that lacks folate transport activity. Mutations in this gene cause biotin-responsive basal ganglia disease (BBGD); a recessive disorder manifested in childhood that progresses to chronic encephalopathy, dystonia, quadriparesis, and death if untreated. Patients with BBGD have bilateral necrosis in the head of the caudate nucleus and in the putamen. Administration of high doses of biotin in the early progression of the disorder eliminates pathological symptoms while delayed treatment results in residual paraparesis, mild cognitive disability, or dystonia. Administration of thiamine is ineffective in the treatment of this disorder. Experiments have failed to show that this protein can transport biotin. Mutations in this gene also cause a Wernicke's-like encephalopathy.[provided by RefSeq, Jan 2010]

ACMG classification

Verdict is Benign. Variant got -8 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.2).
• BP6: Variant 2-227699325-C-A is Benign according to our data. Variant chr2-227699325-C-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 334882.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=2, Uncertain_significance=1, Benign=1}.
• BP7: Synonymous conserved (PhyloP=-0.226 with no splicing effect.
• BS2: High Homozygotes in GnomAdExome4 at 2 AR gene

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
SLC19A3	NM_025243.4	c.390G>T	p.Val130=	synonymous_variant	3/6	ENST00000644224.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SLC19A3	ENST00000644224.2	c.390G>T	p.Val130=	synonymous_variant	3/6		NM_025243.4	P1

Frequencies

GnomAD3 genomes AF: 0.000171 AC: 26 AN: 152134 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: 0.00186

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.000235

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.000374 AC: 94 AN: 251404 Hom.: 0 AF XY: 0.000442 AC XY: 60 AN XY: 135876

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000289

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00131

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.000457

Gnomad OTH exome AF: 0.000163

GnomAD4 exome AF: 0.000359 AC: 525 AN: 1461886 Hom.: 2 Cov.: 33 AF XY: 0.000408 AC XY: 297 AN XY: 727246

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000224

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00152

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.000341

Gnomad4 OTH exome AF: 0.000232

GnomAD4 genome AF: 0.000171 AC: 26 AN: 152134 Hom.: 0 Cov.: 32 AF XY: 0.000229 AC XY: 17 AN XY: 74304

Gnomad4 AFR AF: 0.0000241

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00186

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.000235

Gnomad4 OTH AF: 0.00

Alfa AF: 0.000278 Hom.: 0

Bravo AF: 0.000204

EpiCase AF: 0.000382

EpiControl AF: 0.000593

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:1 Benign:3

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Biotin-responsive basal ganglia disease Uncertain:1 Benign:1

Uncertain significance, criteria provided, single submitter	clinical testing	Illumina Laboratory Services, Illumina	Jan 13, 2018	This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -
Likely benign, criteria provided, single submitter	clinical testing	Invitae	Jan 19, 2024	- -

not provided Benign:2

Likely benign, criteria provided, single submitter	clinical testing	CeGaT Center for Human Genetics Tuebingen	Nov 01, 2020	- -
Benign, criteria provided, single submitter	clinical testing	GeneDx	Mar 03, 2015	- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.20
CADD	Benign	7.1
DANN	Benign	0.78

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: rs376187918; hg19: chr2-228564041;