20-761240-T-C

Variant names:

• chr20-761240-T-C
• rs754753126
• NM_033409.4:c.1198-2A>G

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PVS1 PM2

The NM_033409.4(SLC52A3):​c.1198-2A>G variant causes a splice acceptor, intron change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000131 in 152,178 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: 𝑓 0.000013 (0 hom., cov: 34)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: SLC52A3 NM_033409.4 splice_acceptor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.67
• Publications: 2 publications found

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: ClinGen, Ambry Genetics, PanelApp Australia, Genomics England PanelApp, G2P, Labcorp Genetics (formerly Invitae)
• progressive bulbar palsy

  Inheritance: AR Classification: MODERATE Submitted by: Ambry Genetics

ACMG classification

Our verdict: Pathogenic. The variant received 10 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease,
• PM2: Very rare variant in population databases, with high coverage

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_033409.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SLC52A3	NM_033409.4	MANE Select	c.1198-2A>G		splice_acceptor intron	N/A	NP_212134.3
	SLC52A3	NM_001370085.1		c.1198-2A>G		splice_acceptor intron	N/A	NP_001357014.1	Q9NQ40-1
	SLC52A3	NM_001370086.1		c.1198-2A>G		splice_acceptor intron	N/A	NP_001357015.1	Q9NQ40-1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SLC52A3	ENST00000645534.1	MANE Select	c.1198-2A>G		splice_acceptor intron	N/A	ENSP00000494193.1	Q9NQ40-1
	SLC52A3	ENST00000381944.5	TSL:2	c.*410A>G		3_prime_UTR	Exon 4 of 4	ENSP00000371370.3	Q9NQ40-2
	SLC52A3	ENST00000217254.11	TSL:5	c.1198-2A>G		splice_acceptor intron	N/A	ENSP00000217254.7	Q9NQ40-1

Frequencies

GnomAD3 genomes AF: 0.0000131 AC: 2 AN: 152178 Hom.: 0 Cov.: 34

Gnomad AFR AF: 0.0000483

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: 0.00

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.00 AC: 0 AN: 149592 AF XY: 0.00

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: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 1394280 Hom.: 0 Cov.: 36 AF XY: 0.00 AC XY: 0 AN XY: 687124

African (AFR) AF: 0.00 AC: 0 AN: 31570

American (AMR) AF: 0.00 AC: 0 AN: 35894

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25114

East Asian (EAS) AF: 0.00 AC: 0 AN: 35852

South Asian (SAS) AF: 0.00 AC: 0 AN: 79250

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 47240

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 4318

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1077318

Other (OTH) AF: 0.00 AC: 0 AN: 57724

GnomAD4 genome AF: 0.0000131 AC: 2 AN: 152178 Hom.: 0 Cov.: 34 AF XY: 0.0000134 AC XY: 1 AN XY: 74354

African (AFR) AF: 0.0000483 AC: 2 AN: 41440

American (AMR) AF: 0.00 AC: 0 AN: 15286

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3470

East Asian (EAS) AF: 0.00 AC: 0 AN: 5182

South Asian (SAS) AF: 0.00 AC: 0 AN: 4834

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10616

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 68030

Other (OTH) AF: 0.00 AC: 0 AN: 2092

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.0000113

ExAC AF: 0.00000960 AC: 1

ClinVar

ClinVar submissions

Significance: Uncertain significance

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
-	1	-	Brown-Vialetto-van Laere syndrome 1 (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.19
CADD	Pathogenic	34
DANN	Uncertain	0.99
Eigen	Pathogenic	1.0
Eigen_PC	Pathogenic	0.84
FATHMM_MKL	Pathogenic	0.99	D
PhyloP100		7.7
GERP RS		4.7
Mutation Taster		=0/100	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.93
SpliceAI score (max)		0.99		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.35		Position offset: -25
DS_AL_spliceai		0.99		Position offset: -2

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

Other links and lift over

dbSNP: rs754753126; hg19: chr20-741884;