rs747823282

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM1BP4BS1_Supporting

The NM_025243.4(SLC19A3):​c.977G>T​(p.Gly326Val) variant causes a missense, splice region change. The variant allele was found at a frequency of 0.0000403 in 1,612,890 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/24 in silico tools predict a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.00015 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000029 ( 0 hom. )

Consequence

SLC19A3
NM_025243.4 missense, splice_region

Scores

4
15
Splicing: ADA: 0.02718
2

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:6O:1

Conservation

PhyloP100: 4.06

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

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 0 ACMG points.

PM1
In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 10 uncertain in NM_025243.4
BP4
Computational evidence support a benign effect (MetaRNN=0.2949767).
BS1
Variant frequency is greater than expected in population amr. GnomAd4 allele frequency = 0.000151 (23/152216) while in subpopulation AMR AF = 0.00144 (22/15272). AF 95% confidence interval is 0.000975. There are 0 homozygotes in GnomAd4. There are 17 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SLC19A3NM_025243.4 linkc.977G>T p.Gly326Val missense_variant, splice_region_variant Exon 3 of 6 ENST00000644224.2 NP_079519.1 Q9BZV2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
SLC19A3ENST00000644224.2 linkc.977G>T p.Gly326Val missense_variant, splice_region_variant Exon 3 of 6 NM_025243.4 ENSP00000495385.1 Q9BZV2

Frequencies

GnomAD3 genomes
AF:
0.000151
AC:
23
AN:
152216
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00144
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:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000558
AC:
14
AN:
250828
AF XY:
0.0000663
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.000289
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000265
Gnomad OTH exome
AF:
0.000163
GnomAD4 exome
AF:
0.0000288
AC:
42
AN:
1460674
Hom.:
0
Cov.:
32
AF XY:
0.0000344
AC XY:
25
AN XY:
726684
show subpopulations
African (AFR)
AF:
0.000120
AC:
4
AN:
33460
American (AMR)
AF:
0.000246
AC:
11
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26130
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39698
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86218
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53100
Middle Eastern (MID)
AF:
0.000922
AC:
5
AN:
5422
European-Non Finnish (NFE)
AF:
0.0000126
AC:
14
AN:
1111606
Other (OTH)
AF:
0.000133
AC:
8
AN:
60316
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.458
Heterozygous variant carriers
0
3
5
8
10
13
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<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:
0.000151
AC:
23
AN:
152216
Hom.:
0
Cov.:
32
AF XY:
0.000229
AC XY:
17
AN XY:
74366
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41464
American (AMR)
AF:
0.00144
AC:
22
AN:
15272
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5198
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10624
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68036
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.521
Heterozygous variant carriers
0
1
2
4
5
6
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<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:
0.00
Hom.:
0
Bravo
AF:
0.000257
ExAC
AF:
0.0000330
AC:
4
EpiCase
AF:
0.000109
EpiControl
AF:
0.000178

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:6Other:1
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Biotin-responsive basal ganglia disease Uncertain:4Other:1
Jan 12, 2018
Illumina Laboratory Services, Illumina
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

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. -

Oct 31, 2018
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jan 10, 2022
Baylor Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

-
GenomeConnect - Brain Gene Registry
Significance:not provided
Review Status:no classification provided
Collection Method:phenotyping only

Variant interpreted as Uncertain significance and reported on 03-25-2018 by Lab Invitae. Assertions are reported exactly as they appear on the patient provided laboratory report. GenomeConnect does not attempt to reinterpret the variant. The IDDRC-CTSA National Brain Gene Registry (BGR) is a study funded by the U.S. National Center for Advancing Translational Sciences (NCATS) and includes 13 Intellectual and Developmental Disability Research Center (IDDRC) institutions. The study is led by Principal Investigator Dr. Philip Payne from Washington University. The BGR is a data commons of gene variants paired with subject clinical information. This database helps scientists learn more about genetic changes and their impact on the brain and behavior. Participation in the Brain Gene Registry requires participation in GenomeConnect. More information about the Brain Gene Registry can be found on the study website - https://braingeneregistry.wustl.edu/. -

Oct 13, 2022
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 valine, which is neutral and non-polar, at codon 326 of the SLC19A3 protein (p.Gly326Val). This variant is present in population databases (rs747823282, gnomAD 0.03%). This variant has not been reported in the literature in individuals affected with SLC19A3-related conditions. ClinVar contains an entry for this variant (Variation ID: 334879). 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: "Tolerated"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C0"). 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. -

Inborn genetic diseases Uncertain:1
Nov 12, 2021
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.977G>T (p.G326V) alteration is located in exon 3 (coding exon 2) of the SLC19A3 gene. This alteration results from a G to T substitution at nucleotide position 977, causing the glycine (G) at amino acid position 326 to be replaced by a valine (V). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

not provided Uncertain:1
Apr 15, 2025
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

In silico analysis indicates 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
0.14
BayesDel_addAF
Benign
-0.12
T
BayesDel_noAF
Benign
-0.11
CADD
Benign
17
DANN
Uncertain
0.99
DEOGEN2
Benign
0.11
T;T;.
Eigen
Benign
0.054
Eigen_PC
Benign
0.18
FATHMM_MKL
Benign
0.68
D
LIST_S2
Uncertain
0.90
.;D;D
M_CAP
Benign
0.075
D
MetaRNN
Benign
0.29
T;T;T
MetaSVM
Benign
-0.45
T
MutationAssessor
Uncertain
2.2
M;M;.
PhyloP100
4.1
PrimateAI
Benign
0.39
T
PROVEAN
Benign
0.95
.;N;.
REVEL
Uncertain
0.45
Sift
Benign
0.23
.;T;.
Sift4G
Benign
0.36
.;T;.
Polyphen
0.24
B;B;.
Vest4
0.20
MutPred
0.64
Loss of catalytic residue at G327 (P = 0.1111);Loss of catalytic residue at G327 (P = 0.1111);.;
MVP
0.95
MPC
0.36
ClinPred
0.10
T
GERP RS
4.9
Varity_R
0.10
gMVP
0.34
Mutation Taster
=78/22
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Benign
0.027
dbscSNV1_RF
Benign
0.34
SpliceAI score (max)
0.020
Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

Other links and lift over

dbSNP: rs747823282; hg19: chr2-228563454; API