20-761240-T-G

Variant names:

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

Variant summary

Our verdict is Pathogenic. The variant received 11 ACMG points: 11P and 0B. PVS1 PM2 PP5

The NM_033409.4(SLC52A3):​c.1198-2A>C variant causes a splice acceptor, intron change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. 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 Pathogenic (no stars).

• Frequency: Genomes: not found (cov: 34)
• Consequence: SLC52A3 NM_033409.4 splice_acceptor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic no assertion criteria provided P:1 O: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: Ambry Genetics, G2P, ClinGen, Genomics England PanelApp, Labcorp Genetics (formerly Invitae), PanelApp Australia
• progressive bulbar palsy

  Inheritance: AR Classification: MODERATE Submitted by: Ambry Genetics

ACMG classification

Our verdict: Pathogenic. The variant received 11 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
• PP5: Variant 20-761240-T-G is Pathogenic according to our data. Variant chr20-761240-T-G is described in ClinVar as Pathogenic. ClinVar VariationId is 210025.Status of the report is no_assertion_criteria_provided, 0 stars.

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

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

Ensembl Transcripts

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

Frequencies

GnomAD3 genomes Cov.: 34

GnomAD4 exome Cov.: 36

GnomAD4 genome Cov.: 34

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1 Other:1

Revision: no assertion criteria provided

Submissions by phenotype

Progressive bulbar palsy of childhood Pathogenic:1

Feb 01, 2011

OMIM

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: literature only

Brown-Vialetto-van Laere syndrome 1 Other:1

GeneReviews

Significance: not provided

Review Status: no classification provided

Collection Method: literature only

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.23
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 (ClinVar)

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		0.36		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;