rs149622425

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 0P and 3B. BP4_ModerateBS1_Supporting

The NM_033409.4(SLC52A3):​c.203G>C​(p.Cys68Ser) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000215 in 1,582,136 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 17/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.00014 ( 0 hom., cov: 31)
Exomes 𝑓: 0.00022 ( 0 hom. )

Consequence

SLC52A3
NM_033409.4 missense

Scores

19

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:4

Conservation

PhyloP100: 0.280

Publications

2 publications found
Variant links:
Genes affected
SLC52A3 (HGNC:16187): (solute carrier family 52 member 3) This gene encodes a riboflavin transporter protein that is strongly expressed in the intestine and likely plays a role in intestinal absorption of riboflavin. The protein is predicted to have eleven transmembrane domains and a cell surface localization signal in the C-terminus. Mutations at this locus have been associated with Brown-Vialetto-Van Laere syndrome and Fazio-Londe disease. [provided by RefSeq, Mar 2012]
SLC52A3 Gene-Disease associations (from GenCC):
  • Brown-Vialetto-van Laere syndrome 1
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, G2P, ClinGen, Genomics England PanelApp, Labcorp Genetics (formerly Invitae), PanelApp Australia
  • progressive bulbar palsy
    Inheritance: AR Classification: MODERATE Submitted by: Ambry Genetics

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -3 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.12685952).
BS1
Variant frequency is greater than expected in population nfe. GnomAd4 allele frequency = 0.000145 (22/152122) while in subpopulation NFE AF = 0.000294 (20/68022). AF 95% confidence interval is 0.000194. There are 0 homozygotes in GnomAd4. There are 6 alleles in the male GnomAd4 subpopulation. Median coverage is 31. 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
SLC52A3NM_033409.4 linkc.203G>C p.Cys68Ser missense_variant Exon 2 of 5 ENST00000645534.1 NP_212134.3 Q9NQ40-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
SLC52A3ENST00000645534.1 linkc.203G>C p.Cys68Ser missense_variant Exon 2 of 5 NM_033409.4 ENSP00000494193.1 Q9NQ40-1

Frequencies

GnomAD3 genomes
AF:
0.000145
AC:
22
AN:
152122
Hom.:
0
Cov.:
31
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000655
Gnomad ASJ
AF:
0.000288
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.000294
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000810
AC:
16
AN:
197594
AF XY:
0.0000855
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.0000572
Gnomad NFE exome
AF:
0.000163
Gnomad OTH exome
AF:
0.000196
GnomAD4 exome
AF:
0.000222
AC:
318
AN:
1430014
Hom.:
0
Cov.:
36
AF XY:
0.000225
AC XY:
159
AN XY:
708040
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33056
American (AMR)
AF:
0.00
AC:
0
AN:
38490
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25388
East Asian (EAS)
AF:
0.00
AC:
0
AN:
38390
South Asian (SAS)
AF:
0.00
AC:
0
AN:
81834
European-Finnish (FIN)
AF:
0.0000195
AC:
1
AN:
51374
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5724
European-Non Finnish (NFE)
AF:
0.000284
AC:
311
AN:
1096444
Other (OTH)
AF:
0.000101
AC:
6
AN:
59314
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.483
Heterozygous variant carriers
0
20
40
61
81
101
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
20
40
60
80
100
<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:
0.000145
AC:
22
AN:
152122
Hom.:
0
Cov.:
31
AF XY:
0.0000808
AC XY:
6
AN XY:
74290
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41412
American (AMR)
AF:
0.0000655
AC:
1
AN:
15268
Ashkenazi Jewish (ASJ)
AF:
0.000288
AC:
1
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5194
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4822
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10614
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.000294
AC:
20
AN:
68022
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.530
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:
0.000155
Hom.:
0
Bravo
AF:
0.0000907
TwinsUK
AF:
0.00
AC:
0
ALSPAC
AF:
0.000519
AC:
2
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000233
AC:
2
ExAC
AF:
0.0000331
AC:
4

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:4
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Uncertain:2
Apr 30, 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 -

-
Breakthrough Genomics, Breakthrough Genomics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:not provided

- -

Inborn genetic diseases Uncertain:1
Jun 01, 2022
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.C68S variant (also known as c.203G>C), located in coding exon 1 of the SLC52A3 gene, results from a G to C substitution at nucleotide position 203. The cysteine at codon 68 is replaced by serine, an amino acid with dissimilar properties. This amino acid position is not well conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Brown-Vialetto-van Laere syndrome 1 Uncertain:1
Dec 18, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces cysteine, which is neutral and slightly polar, with serine, which is neutral and polar, at codon 68 of the SLC52A3 protein (p.Cys68Ser). This variant is present in population databases (rs149622425, gnomAD 0.02%). This variant has not been reported in the literature in individuals affected with SLC52A3-related conditions. ClinVar contains an entry for this variant (Variation ID: 452583). 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) has been performed for this missense variant. However, the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on SLC52A3 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. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.11
BayesDel_addAF
Benign
-0.18
T
BayesDel_noAF
Benign
-0.23
CADD
Benign
13
DANN
Benign
0.82
DEOGEN2
Benign
0.0033
T;T;.;T;T
Eigen
Benign
-0.27
Eigen_PC
Benign
-0.10
FATHMM_MKL
Benign
0.76
D
LIST_S2
Benign
0.56
.;.;T;.;T
M_CAP
Benign
0.018
T
MetaRNN
Benign
0.13
T;T;T;T;T
MetaSVM
Benign
-0.42
T
MutationAssessor
Benign
1.6
L;L;L;L;L
PhyloP100
0.28
PrimateAI
Benign
0.31
T
PROVEAN
Benign
-0.63
.;.;N;N;.
REVEL
Benign
0.28
Sift
Benign
0.41
.;.;T;T;.
Sift4G
Benign
0.42
.;T;T;T;.
Polyphen
0.050
B;B;B;B;B
Vest4
0.10, 0.10
MutPred
0.39
Gain of disorder (P = 1e-04);Gain of disorder (P = 1e-04);Gain of disorder (P = 1e-04);Gain of disorder (P = 1e-04);Gain of disorder (P = 1e-04);
MVP
0.69
MPC
0.39
ClinPred
0.032
T
GERP RS
4.8
PromoterAI
-0.015
Neutral
Varity_R
0.090
gMVP
0.46
Mutation Taster
=94/6
polymorphism

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

Other links and lift over

dbSNP: rs149622425; hg19: chr20-746216; API