rs754320812

Variant summary

Our verdict is Pathogenic. The variant received 16 ACMG points: 16P and 0B. PM1PM2PP3_StrongPP5_Very_Strong

The NM_001363118.2(SLC52A2):​c.935T>C​(p.Leu312Pro) variant causes a missense change. The variant allele was found at a frequency of 0.0000859 in 1,606,368 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 Likely pathogenic (★★).

Frequency

Genomes: 𝑓 0.000046 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000090 ( 0 hom. )

Consequence

SLC52A2
NM_001363118.2 missense

Scores

13
4
1

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:5O:1

Conservation

PhyloP100: 6.19

Publications

11 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 16 ACMG points.

PM1
In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 9 uncertain in NM_001363118.2
PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.977
PP5
Variant 8-144360427-T-C is Pathogenic according to our data. Variant chr8-144360427-T-C is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 210041.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SLC52A2NM_001363118.2 linkc.935T>C p.Leu312Pro missense_variant Exon 3 of 5 ENST00000643944.2 NP_001350047.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
SLC52A2ENST00000643944.2 linkc.935T>C p.Leu312Pro missense_variant Exon 3 of 5 NM_001363118.2 ENSP00000496184.2 Q9HAB3

Frequencies

GnomAD3 genomes
AF:
0.0000460
AC:
7
AN:
152284
Hom.:
0
Cov.:
33
show subpopulations
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:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000882
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000245
AC:
6
AN:
245242
AF XY:
0.0000300
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:
0.00
Gnomad NFE exome
AF:
0.0000445
Gnomad OTH exome
AF:
0.000165
GnomAD4 exome
AF:
0.0000901
AC:
131
AN:
1454084
Hom.:
0
Cov.:
31
AF XY:
0.0000732
AC XY:
53
AN XY:
723638
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33478
American (AMR)
AF:
0.00
AC:
0
AN:
44716
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26124
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39694
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86256
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
45780
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.000115
AC:
128
AN:
1111926
Other (OTH)
AF:
0.0000497
AC:
3
AN:
60342
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.488
Heterozygous variant carriers
0
10
20
29
39
49
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
10
20
30
40
50
<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:
0.0000460
AC:
7
AN:
152284
Hom.:
0
Cov.:
33
AF XY:
0.0000538
AC XY:
4
AN XY:
74400
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41482
American (AMR)
AF:
0.00
AC:
0
AN:
15292
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5206
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4838
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10628
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000882
AC:
6
AN:
68046
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.539
Heterozygous variant carriers
0
1
2
2
3
4
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:
0.0000416
Hom.:
0
Bravo
AF:
0.0000416
ExAC
AF:
0.0000330
AC:
4
EpiCase
AF:
0.00
EpiControl
AF:
0.000178

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:5Other:1
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Brown-Vialetto-van Laere syndrome 2 Pathogenic:2Other:1
Sep 06, 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 312 of the SLC52A2 protein (p.Leu312Pro). This variant is present in population databases (rs754320812, gnomAD 0.005%). This missense change has been observed in individuals with Brown-Vialetto-Van Laere syndrome (PMID: 24253200, 29053833). ClinVar contains an entry for this variant (Variation ID: 210041). 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 SLC52A2 protein function. Experimental studies have shown that this missense change affects SLC52A2 function (PMID: 24253200). For these reasons, this variant has been classified as Pathogenic. -

Nov 22, 2022
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: GPR172A (SLC52A2) c.935T>C (p.Leu312Pro) results in a non-conservative amino acid change in the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 2.5e-05 in 276638 control chromosomes (gnomAD). c.935T>C has been reported in the literature as a biallelic genotype in individuals affected with Brown-Vialetto Laere Syndrome (e.g. Foley_2014, Manole_2017, Marioli_2020). These data indicate that the variant is likely to be associated with disease. At least two publications report experimental evidence evaluating an impact on protein function (e.g. Foley_2014, Console_2022). The most pronounced variant effect results in approximately 40-50% of normal 3H-Riboflavin transport activity and displays a reduced binding affinity compared to the wildtype protein. Five submitters have provided clinical-significance assessments for this variant to ClinVar after 2014. All laboratories classified the variant as either pathogenic (n=2) or likely pathogenic (n=3). Based on the evidence outlined above, the variant was classified as likely pathogenic. -

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

- -

not provided Pathogenic:2
May 02, 2025
GeneDx
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Published functional studies demonstrate a damaging effect: reduced riboflavin uptake and reduced riboflavin transporter protein expression (PMID: 24253200); Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 26633542, 34428344, 24253200, 29053833, 26072523, 32855765, 38278809, 39113759, 33468503, 40134705, 33036493, 28116953) -

May 19, 2016
Center for Pediatric Genomic Medicine, Children's Mercy Hospital and Clinics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Inborn genetic diseases Pathogenic:1
Aug 16, 2023
Ambry Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.935T>C (p.L312P) alteration is located in exon 3 (coding exon 2) of the SLC52A2 gene. This alteration results from a T to C substitution at nucleotide position 935, causing the leucine (L) at amino acid position 312 to be replaced by a proline (P). Based on data from gnomAD, the C allele has an overall frequency of 0.003% (7/276638) total alleles studied. The highest observed frequency was 0.014% (1/7158) of Other alleles. This alteration has been reported in the homozygous state, and in conjunction with another alteration in SLC52A2, in multiple individuals with clinical features of Brown-Vialetto-Van Laere syndrome (Foley, 2014; Manole, 2017; Allison, 2017; Ambry internal data). This amino acid position is highly conserved in available vertebrate species. In vitro functional analysis of the p.L312P alteration showed a moderate decrease in 3H-transport activity compared with wild-type SLC52A2 (Foley, 2014). This alteration is predicted to be deleterious by in silico analysis. Based on the available evidence, this alteration is classified as pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.79
BayesDel_addAF
Pathogenic
0.32
D
BayesDel_noAF
Pathogenic
0.36
CADD
Pathogenic
27
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.61
D;D;.;D;D;D;D
Eigen
Pathogenic
0.78
Eigen_PC
Pathogenic
0.70
FATHMM_MKL
Pathogenic
0.98
D
M_CAP
Pathogenic
0.84
D
MetaRNN
Pathogenic
0.98
D;D;D;D;D;D;D
MetaSVM
Uncertain
0.55
D
MutationAssessor
Pathogenic
3.3
M;M;.;M;M;M;M
PhyloP100
6.2
PrimateAI
Pathogenic
0.82
D
PROVEAN
Pathogenic
-6.8
D;D;D;D;D;D;.
REVEL
Pathogenic
0.98
Sift
Uncertain
0.0010
D;D;D;D;D;D;.
Sift4G
Pathogenic
0.0010
D;D;D;D;D;D;.
Polyphen
1.0
D;D;.;D;D;D;D
Vest4
0.98
MVP
0.83
MPC
0.69
ClinPred
0.94
D
GERP RS
4.7
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.96
gMVP
0.94
Mutation Taster
=0/100
disease causing (ClinVar)

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: rs754320812; hg19: chr8-145584087; API