chr2-227696037-C-T

Variant names:

Variant summary

Our verdict is Uncertain significance. The variant received 1 ACMG points: 2P and 1B. PM2BP4

The NM_025243.4(SLC19A3):c.1024G>A(p.Asp342Asn) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000558 in 1,614,068 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 16/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.000033 ( 0 hom., cov: 33)

Exomes 𝑓: 0.0000027 ( 0 hom. )

Consequence

SLC19A3
NM_025243.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 1.09

Publications

0 publications found

Variant links:

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]

SLC19A3 Gene-Disease associations (from GenCC):

biotin-responsive basal ganglia disease
Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Orphanet, Genomics England PanelApp, G2P
Leigh syndrome
Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
infantile spams-psychomotor retardation-progressive brain atrophy-basal ganglia disease syndrome
Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
Leigh syndrome with leukodystrophy
Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
thiamine-responsive encephalopathy
Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

SLC19A3 links:

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 1 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (MetaRNN=0.28759116).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SLC19A3	NM_025243.4 link	c.1024G>A	p.Asp342Asn	missense_variant	Exon 4 of 6	ENST00000644224.2	NP_079519.1	Q9BZV2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SLC19A3	ENST00000644224.2 link	c.1024G>A	p.Asp342Asn	missense_variant	Exon 4 of 6		NM_025243.4	ENSP00000495385.1		Q9BZV2

Frequencies

GnomAD3 genomes

AF:

0.0000263

AC:

AN:

152066

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000966

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:

0.00

Gnomad OTH

AF:

0.00

GnomAD2 exomes

AF:

0.00000398

AC:

AN:

251432

AF XY:

0.00

show subpopulations

Gnomad AFR exome

AF:

0.0000615

Gnomad AMR exome

AF:

0.00

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:

0.00000274

AC:

AN:

1461884

Hom.:

Cov.:

AF XY:

0.00000550

AC XY:

AN XY:

727244

show subpopulations

African (AFR)

AF:

0.000119

AC:

AN:

33478

American (AMR)

AF:

0.00

AC:

AN:

44724

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

26134

East Asian (EAS)

AF:

0.00

AC:

AN:

39698

South Asian (SAS)

AF:

0.00

AC:

AN:

86258

European-Finnish (FIN)

AF:

0.00

AC:

AN:

53420

Middle Eastern (MID)

AF:

0.00

AC:

AN:

5768

European-Non Finnish (NFE)

AF:

0.00

AC:

AN:

1112008

Other (OTH)

AF:

0.00

AC:

AN:

60396

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.488

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Exome Het

Variant carriers

<30

30-35

35-40

40-45

45-50

50-55

55-60

60-65

65-70

70-75

75-80

>80

Age

GnomAD4 genome

AF:

0.0000329

AC:

AN:

152184

Hom.:

Cov.:

AF XY:

0.0000403

AC XY:

AN XY:

74400

show subpopulations

African (AFR)

AF:

0.000120

AC:

AN:

41526

American (AMR)

AF:

0.00

AC:

AN:

15274

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

3470

East Asian (EAS)

AF:

0.00

AC:

AN:

5172

South Asian (SAS)

AF:

0.00

AC:

AN:

4804

European-Finnish (FIN)

AF:

0.00

AC:

AN:

10602

Middle Eastern (MID)

AF:

0.00

AC:

AN:

294

European-Non Finnish (NFE)

AF:

0.00

AC:

AN:

68022

Other (OTH)

AF:

0.00

AC:

AN:

2108

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.512

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Genome Het

Variant carriers

<30

30-35

35-40

40-45

45-50

50-55

55-60

60-65

65-70

70-75

75-80

>80

Age

Alfa

AF:

0.0000329

Hom.:

Bravo

AF:

0.0000416

Asia WGS

AF:

0.000289

AC:

AN:

3478

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Biotin-responsive basal ganglia disease

Uncertain:1

Sep 01, 2021

Labcorp Genetics (formerly Invitae), Labcorp

Significance:Uncertain significance

Review Status:criteria provided, single submitter

Collection Method:clinical testing

This sequence change replaces aspartic acid with asparagine at codon 342 of the SLC19A3 protein (p.Asp342Asn). The aspartic acid residue is moderately conserved and there is a small physicochemical difference between aspartic acid and asparagine. This variant is not present in population databases (ExAC no frequency). This variant has not been reported in the literature in individuals affected with SLC19A3-related conditions. Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Tolerated"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0". The asparagine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. 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. -

not provided

Uncertain:1

May 27, 2025

GeneDx

Significance:Uncertain significance

Review Status:criteria provided, single submitter

Collection Method:clinical testing

Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis suggests that this missense variant does not alter protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.087

BayesDel_addAF

Benign

-0.23

BayesDel_noAF

Benign

-0.39

CADD

Benign

(source)

DANN

Uncertain

1.0

DEOGEN2

Benign

0.24

T;T;.

Eigen

Benign

-0.26

Eigen_PC

Benign

-0.12

FATHMM_MKL

Uncertain

0.90

LIST_S2

Benign

0.86

.;D;D

M_CAP

Benign

0.027

MetaRNN

Benign

0.29

T;T;T

MetaSVM

Benign

-0.50

MutationAssessor

Benign

1.6

L;L;.

PhyloP100

1.1

PrimateAI

Benign

0.44

PROVEAN

Benign

-1.9

.;N;.

REVEL

Benign

0.27

Sift

Benign

0.11

.;T;.

Sift4G

Benign

0.16

.;T;.

Polyphen

0.025

B;B;.

Vest4

0.29

MVP

0.89

MPC

0.075

ClinPred

0.41

GERP RS

3.4

Varity_R

0.14

gMVP

0.13

Mutation Taster

=63/37

polymorphism

(source)

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

You must be logged in to view publications. This limit was set because tens of millions (!) of queries from AI bots are generated daily.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

Publications

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

Age Distribution

Age Distribution

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

Other links and lift over