chr20-765401-G-T

Position:

chr20-765401-G-T

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2PP3_Moderate

The NM_033409.4(SLC52A3):c.374C>A(p.Thr125Asn) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000644 in 1,613,978 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 Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.000039 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000067 ( 0 hom. )

Consequence

SLC52A3
NM_033409.4 missense

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1U:3

Conservation

PhyloP100: 9.91

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 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 4 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

PP3

MetaRNN computational evidence supports a deleterious effect, 0.871

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
SLC52A3	NM_033409.4 linkuse as main transcript	c.374C>A	p.Thr125Asn	missense_variant	2/5	ENST00000645534.1	NP_212134.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
SLC52A3	ENST00000645534.1 linkuse as main transcript	c.374C>A	p.Thr125Asn	missense_variant	2/5		NM_033409.4	ENSP00000494193	P1	Q9NQ40-1

Frequencies

GnomAD3 genomes

AF:

0.0000394

AC:

AN:

152174

Hom.:

Cov.:

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:

0.0000882

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000199

AC:

AN:

250912

Hom.:

AF XY:

0.0000295

AC XY:

AN XY:

135666

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 SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000441

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000670

AC:

AN:

1461804

Hom.:

Cov.:

AF XY:

0.0000743

AC XY:

AN XY:

727194

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000836

Gnomad4 OTH exome

AF:

0.0000828

GnomAD4 genome

AF:

0.0000394

AC:

AN:

152174

Hom.:

Cov.:

AF XY:

0.0000269

AC XY:

AN XY:

74338

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000882

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000579

Hom.:

Bravo

AF:

0.0000264

ExAC

AF:

0.00000824

AC:

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:1Uncertain:3

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

not provided

Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

GeneDx

Dec 18, 2023

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: 29053833, 29961494, 34395718, 34662687) -

not specified

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

May 06, 2024

Variant summary: C20orf54 c.374C>A (p.Thr125Asn) 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 2.8e-05 in 282314 control chromosomes. c.374C>A has been reported in the literature in individuals affected with Brown-Vialetto Laere Syndrome 1/ riboflavin transporter deficiency (e.g. Manole_2017, Chaya_2017, Frederick_2021, Elks_2023) . These data indicate that the variant may be associated with disease. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. The following publications have been ascertained in the context of this evaluation (PMID: 29053833, 29961494, 34395718, 37116404). ClinVar contains an entry for this variant (Variation ID: 1338936). Based on the evidence outlined above, the variant was classified as VUS-possibly pathogenic. -

Inborn genetic diseases

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Oct 20, 2022

The c.374C>A (p.T125N) alteration is located in exon 2 (coding exon 1) of the SLC52A3 gene. This alteration results from a C to A substitution at nucleotide position 374, causing the threonine (T) at amino acid position 125 to be replaced by an asparagine (N). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Brown-Vialetto-van Laere syndrome 1

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

May 05, 2022

This sequence change replaces threonine, which is neutral and polar, with asparagine, which is neutral and polar, at codon 125 of the SLC52A3 protein (p.Thr125Asn). This variant is present in population databases (rs767263985, gnomAD 0.006%). This missense change has been observed in individual(s) with Brown-Vialetto-Van Laere syndrome (PMID: 29053833). 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: "Probably 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. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Uncertain

0.53

BayesDel_addAF

Uncertain

0.075

BayesDel_noAF

Uncertain

0.0

CADD

Pathogenic

DANN

Uncertain

0.99

DEOGEN2

Benign

0.32

T;T;.;T;T

Eigen

Pathogenic

0.93

Eigen_PC

Pathogenic

0.90

FATHMM_MKL

Pathogenic

0.99

LIST_S2

Uncertain

0.96

.;.;D;.;D

M_CAP

Uncertain

0.28

MetaRNN

Pathogenic

0.87

D;D;D;D;D

MetaSVM

Uncertain

0.79

MutationAssessor

Pathogenic

3.4

M;M;M;M;M

MutationTaster

Benign

1.0

D;D

PrimateAI

Uncertain

0.68

PROVEAN

Uncertain

-3.9

.;.;D;D;.

REVEL

Pathogenic

0.74

Sift

Uncertain

0.0070

.;.;D;D;.

Sift4G

Uncertain

0.0080

.;D;D;D;.

Polyphen

1.0

D;D;D;D;D

Vest4

0.93, 0.93

MVP

0.90

MPC

1.1

ClinPred

0.82

GERP RS

5.5

Varity_R

0.59

gMVP

0.93

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

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over