rs148234606

Variant summary

Our verdict is Pathogenic. The variant received 11 ACMG points: 12P and 1B. PP3_StrongPP5_Very_StrongBS1_Supporting

The NM_001363118.2(SLC52A2):​c.1016T>C​(p.Leu339Pro) variant causes a missense change. The variant allele was found at a frequency of 0.000177 in 1,601,890 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★). Synonymous variant affecting the same amino acid position (i.e. L339L) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000079 ( 0 hom., cov: 33)
Exomes 𝑓: 0.00019 ( 0 hom. )

Consequence

SLC52A2
NM_001363118.2 missense

Scores

8
9
1

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:10O:1

Conservation

PhyloP100: 6.15

Publications

17 publications found
Variant links:
Genes affected
SLC52A2 (HGNC:30224): (solute carrier family 52 member 2) This gene encodes a membrane protein which belongs to the riboflavin transporter family. In humans, riboflavin must be obtained by intestinal absorption because it cannot be synthesized by the body. The water-soluble vitamin riboflavin is processed to the coenzymes flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD) which then act as intermediaries in many cellular metabolic reactions. Paralogous members of the riboflavin transporter gene family are located on chromosomes 17 and 20. Unlike other members of this family, this gene has higher expression in brain tissue than small intestine. Alternative splicing of this gene results in multiple transcript variants encoding the same protein. Mutations in this gene have been associated with Brown-Vialetto-Van Laere syndrome 2 - an autosomal recessive progressive neurologic disorder characterized by deafness, bulbar dysfunction, and axial and limb hypotonia. [provided by RefSeq, Jul 2012]
SLC52A2 Gene-Disease associations (from GenCC):
  • Brown-Vialetto-van Laere syndrome 2
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: ClinGen, Genomics England PanelApp, PanelApp Australia, Labcorp Genetics (formerly Invitae), G2P

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 11 ACMG points.

PP3
MetaRNN computational evidence supports a deleterious effect, 0.95
PP5
Variant 8-144360604-T-C is Pathogenic according to our data. Variant chr8-144360604-T-C is described in ClinVar as Pathogenic. ClinVar VariationId is 39577.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
BS1
Variant frequency is greater than expected in population nfe. GnomAdExome4 allele frequency = 0.000187 (271/1449690) while in subpopulation NFE AF = 0.000236 (262/1110908). AF 95% confidence interval is 0.000212. There are 0 homozygotes in GnomAdExome4. There are 126 alleles in the male GnomAdExome4 subpopulation. Median coverage is 46. 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
SLC52A2NM_001363118.2 linkc.1016T>C p.Leu339Pro missense_variant Exon 4 of 5 ENST00000643944.2 NP_001350047.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
SLC52A2ENST00000643944.2 linkc.1016T>C p.Leu339Pro missense_variant Exon 4 of 5 NM_001363118.2 ENSP00000496184.2 Q9HAB3

Frequencies

GnomAD3 genomes
AF:
0.0000788
AC:
12
AN:
152200
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00
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:
0.000176
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000703
AC:
17
AN:
241950
AF XY:
0.0000683
show subpopulations
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:
0.000134
Gnomad OTH exome
AF:
0.000166
GnomAD4 exome
AF:
0.000187
AC:
271
AN:
1449690
Hom.:
0
Cov.:
46
AF XY:
0.000175
AC XY:
126
AN XY:
721568
show subpopulations
African (AFR)
AF:
0.0000299
AC:
1
AN:
33446
American (AMR)
AF:
0.0000224
AC:
1
AN:
44592
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26020
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39664
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86080
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
42994
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5762
European-Non Finnish (NFE)
AF:
0.000236
AC:
262
AN:
1110908
Other (OTH)
AF:
0.000116
AC:
7
AN:
60224
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.485
Heterozygous variant carriers
0
20
41
61
82
102
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:
0.0000788
AC:
12
AN:
152200
Hom.:
0
Cov.:
33
AF XY:
0.0000269
AC XY:
2
AN XY:
74354
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41460
American (AMR)
AF:
0.00
AC:
0
AN:
15284
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5184
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4834
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10620
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.000176
AC:
12
AN:
68026
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.467
Heterozygous variant carriers
0
1
2
3
4
5
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:
0.000108
Hom.:
0
Bravo
AF:
0.0000869
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000233
AC:
2
ExAC
AF:
0.0000659
AC:
8
EpiCase
AF:
0.0000545
EpiControl
AF:
0.000119

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:10Other:1
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Brown-Vialetto-van Laere syndrome 2 Pathogenic:7Other:1
Jan 01, 2014
OMIM
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:literature only

- -

Mar 25, 2015
Duke University Health System Sequencing Clinic, Duke University Health System
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:research

- -

-
GeneReviews
Significance:not provided
Review Status:no classification provided
Collection Method:literature only

- -

Aug 30, 2022
Revvity Omics, Revvity
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Feb 03, 2023
Greenwood Genetic Center Diagnostic Laboratories, Greenwood Genetic Center
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

PS3, PM2, PM3_Strong, PP3 -

Dec 25, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces leucine, which is neutral and non-polar, with proline, which is neutral and non-polar, at codon 339 of the SLC52A2 protein (p.Leu339Pro). This variant is present in population databases (rs148234606, gnomAD 0.01%). This missense change has been observed in individuals with Brown-Vialetto-Van Laere syndrome (PMID: 22864630, 24253200, 25807286, 27148561). ClinVar contains an entry for this variant (Variation ID: 39577). 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 SLC52A2 protein function with a positive predictive value of 95%. Experimental studies have shown that this missense change affects SLC52A2 function (PMID: 22864630, 24253200, 25798182). For these reasons, this variant has been classified as Pathogenic. -

Jun 11, 2022
Baylor Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

May 21, 2020
Victorian Clinical Genetics Services, Murdoch Childrens Research Institute
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

A heterozygous missense variant was identified, NM_001253816.1(SLC52A2):c.1016T>C in exon 4 of the SLC52A2 gene. This substitution is predicted to create a moderate amino acid change from a leucine to a proline at position 339 of the protein; NP_001240745.1(SLC52A2):p.(Leu339Pro). The leucine at this position has moderate conservation (100 vertebrates, UCSC), and is located within a DUF1011 (NCBI, PDB). In silico software predicts this variant to be damaging (PolyPhen2, PROVEAN, MutationAssessor, FATHMM). The variant is present in the gnomAD population database at a global population frequency of 0.0066% (18 heterozygotes, 0 homozygotes) with a European sub-population frequency of 0.013%. This variant has been previously reported as pathogenic in patients with Brown-Vialetto-Van Laere syndrome (ClinVar, Petrovski, S. et al. (2015), Haack, T. B. et al. (2012)). It has also been shown to segregate with disease in one family (Foley, A. R. et al. (2014)). In addition, functional studies show that this variant causes significantly reduced riboflavin uptake and abolishes protein expression (Foley, A. R. et al. (2014)). Based on information available at the time of curation, this variant has been classified as PATHOGENIC. Legend: (P) - Pathogenic, (N) - Neutral, (B) - Benign -

SLC52A2-related disorder Pathogenic:1
Jun 04, 2024
PreventionGenetics, part of Exact Sciences
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

The SLC52A2 c.1016T>C variant is predicted to result in the amino acid substitution p.Leu339Pro. This variant has been reported to be causative for Brown-Vialetto-van Laere Syndrome (Haack et al. 2012. PubMed ID: 22864630; Foley et al. 2014. PubMed ID: 24253200). A functional study showed that this variant significantly decreased the riboflavin transporter 3 activity (Haack et al. 2012. PubMed ID: 22864630). In addition, at PreventionGenetics, we have observed this variant in the compound heterozygous state with a frameshift pathogenic variant in trans in a different patient with Brown-Vialetto-van Laere Syndrome. This variant is reported in 0.013% of alleles in individuals of European (Non-Finnish) descent in gnomAD. This variant is interpreted as pathogenic. -

Inborn genetic diseases Pathogenic:1
Dec 11, 2019
Ambry Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.L339P variant (also known as c.1016T>C), located in coding exon 3 of the SLC52A2 gene, results from a T to C substitution at nucleotide position 1016. The leucine at codon 339 is replaced by proline, an amino acid with similar properties. This alteration has been reported in the compound heterozygous state in multiple individuals diagnosed with Brown-Vialetto-Van Laere syndrome (Foley AR et al. Brain, 2014 Jan;137:44-56; Haack TB et al. J. Inherit. Metab. Dis., 2012 Nov;35:943-8; Bansagi B et al. Neurology, 2017 Mar;88:1226-1234; Manole A et al. Brain, 2017 11;140:2820-2837; Petrovski S et al. Cold Spring Harb Mol Case Stud, 2015 Oct;1:a000257). In vitro functional analysis of this alteration in HEK239 cells showed a significant decrease in hRFT3 riboflavin transporter activity compared to wild type cells (Haack TB et al. J. Inherit. Metab. Dis., 2012 Nov;35:943-8). It was additionally shown that this alteration leads to decreased expression in plasma membranes and abolished uptake of 3H-riboflavin (Foley AR et al. Brain, 2014 Jan;137:44-56). Based on the supporting evidence, this alteration is interpreted as a disease-causing mutation. -

not provided Pathogenic:1
Jun 26, 2022
GeneDx
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Published functional studies demonstrate reduced or absent riboflavin transport activity (Haack et al., 2012; Foley et al., 2014); Not observed at a significant frequency in large population cohorts (gnomAD); This variant is associated with the following publications: (PMID: 22864630, 24253200, 27148561, 28251916, 25798182, 27702554, 25807286, 23107375, 32909658) -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.51
BayesDel_addAF
Pathogenic
0.21
D
BayesDel_noAF
Pathogenic
0.31
CADD
Uncertain
25
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.55
D;D;.;D;D;D;D
Eigen
Uncertain
0.49
Eigen_PC
Uncertain
0.35
FATHMM_MKL
Pathogenic
0.99
D
M_CAP
Pathogenic
0.58
D
MetaRNN
Pathogenic
0.95
D;D;D;D;D;D;D
MetaSVM
Uncertain
0.38
D
MutationAssessor
Pathogenic
3.2
M;M;.;M;M;M;M
PhyloP100
6.2
PrimateAI
Uncertain
0.54
T
PROVEAN
Pathogenic
-5.5
D;D;.;D;D;D;.
REVEL
Pathogenic
0.82
Sift
Uncertain
0.011
D;D;.;D;D;D;.
Sift4G
Uncertain
0.0020
D;D;.;D;D;D;.
Polyphen
1.0
D;D;.;D;D;D;D
Vest4
0.97
MVP
0.76
MPC
0.69
ClinPred
0.90
D
GERP RS
4.7
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.1
Varity_R
0.93
gMVP
0.93
Mutation Taster
=0/100
disease causing (ClinVar)

Splicing

Name
Calibrated prediction
Score
Prediction
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: rs148234606; hg19: chr8-145584264; API