12-57626790-C-G

Position:

chr12-57626790-C-G

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 3P and 1B. PM2PP5BP4

The ENST00000341156.9(B4GALNT1):c.1556G>C(p.Arg519Pro) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000867 in 1,614,076 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 12/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. R519R) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000059 ( 0 hom., cov: 32)

Exomes 𝑓: 0.0000034 ( 0 hom. )

Consequence

B4GALNT1
ENST00000341156.9 missense

Scores

Clinical Significance

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

Conservation

PhyloP100: 1.73

Variant links:

Genes affected

B4GALNT1 (HGNC:4117): (beta-1,4-N-acetyl-galactosaminyltransferase 1) GM2 and GD2 gangliosides are sialic acid-containing glycosphingolipids. GalNAc-T is the enzyme involved in the biosynthesis of G(M2) and G(D2) glycosphingolipids. GalNAc-T catalyzes the transfer of GalNAc into G(M3) and G(D3) by a beta-1,4 linkage, resulting in the synthesis of G(M2) and G(D2), respectively. Three transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Feb 2013]

B4GALNT1 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 2 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

PP5

Variant 12-57626790-C-G is Pathogenic according to our data. Variant chr12-57626790-C-G is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 848217.We mark this variant Likely_pathogenic, oryginal submissions are: {Pathogenic=1, Uncertain_significance=1}.

BP4

Computational evidence support a benign effect (MetaRNN=0.24700898). . Strength limited to SUPPORTING due to the PP5.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
B4GALNT1	NM_001478.5 linkuse as main transcript	c.1556G>C	p.Arg519Pro	missense_variant	11/11	ENST00000341156.9	NP_001469.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
B4GALNT1	ENST00000341156.9 linkuse as main transcript	c.1556G>C	p.Arg519Pro	missense_variant	11/11	1	NM_001478.5	ENSP00000341562	P1	Q00973-1

Frequencies

GnomAD3 genomes

AF:

0.0000591

AC:

AN:

152188

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000241

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.000458

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:

0.000478

GnomAD3 exomes

AF:

0.00000398

AC:

AN:

251486

Hom.:

AF XY:

0.00

AC XY:

AN XY:

135916

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.0000289

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:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000342

AC:

AN:

1461888

Hom.:

Cov.:

AF XY:

0.00000275

AC XY:

AN XY:

727246

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.000112

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:

0.00

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000591

AC:

AN:

152188

Hom.:

Cov.:

AF XY:

0.0000403

AC XY:

AN XY:

74360

show subpopulations

Gnomad4 AFR

AF:

0.0000241

Gnomad4 AMR

AF:

0.000458

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.000478

Alfa

AF:

0.0000282

Hom.:

Bravo

AF:

0.000196

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:1Uncertain:1

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

not provided

Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

GeneDx

Apr 26, 2024

Published functional studies demonstrate that the R519P variant leads to a loss of function with no GM2 biosynthesis detected (PMID: 35775650); Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis indicates that this missense variant does not alter protein structure/function; This variant is associated with the following publications: (PMID: 35775650) -

Spastic paraplegia

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Aug 23, 2022

This sequence change replaces arginine, which is basic and polar, with proline, which is neutral and non-polar, at codon 519 of the B4GALNT1 protein (p.Arg519Pro). This variant is present in population databases (no rsID available, gnomAD 0.003%). This variant has not been reported in the literature in individuals affected with B4GALNT1-related conditions. ClinVar contains an entry for this variant (Variation ID: 848217). 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: "Possibly 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

0.49

BayesDel_addAF

Benign

-0.090

BayesDel_noAF

Benign

-0.28

CADD

Benign

DANN

Uncertain

0.98

DEOGEN2

Benign

0.41

T;.

Eigen

Benign

0.019

Eigen_PC

Benign

0.069

FATHMM_MKL

Benign

0.66

LIST_S2

Uncertain

0.87

D;T

M_CAP

Benign

0.0093

MetaRNN

Benign

0.25

T;T

MetaSVM

Benign

-1.1

MutationAssessor

Benign

1.7

L;.

MutationTaster

Benign

0.88

N;N

PrimateAI

Uncertain

0.49

PROVEAN

Benign

-1.3

N;N

REVEL

Benign

0.11

Sift

Benign

0.27

T;T

Sift4G

Benign

0.28

T;T

Polyphen

0.84

P;.

Vest4

0.48

MutPred

0.42

Gain of catalytic residue at F522 (P = 0.0019);.;

MVP

0.33

MPC

1.8

ClinPred

0.70

GERP RS

2.8

Varity_R

0.41

gMVP

0.86

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