rs200503833

Positions:

Variant summary

Our verdict is Likely pathogenic. Variant got 7 ACMG points: 7P and 0B. PVS1_StrongPM2PP5

The NM_007255.3(B4GALT7):c.38G>A(p.Trp13Ter) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000618 in 1,385,202 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 0.00026 ( 0 hom., cov: 31)

Exomes 𝑓: 0.00066 ( 0 hom. )

Consequence

B4GALT7
NM_007255.3 stop_gained

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:4U:3

Conservation

PhyloP100: 1.99

Variant links:

Genes affected

B4GALT7 (HGNC:930): (beta-1,4-galactosyltransferase 7) This gene is a member of the beta-1,4-galactosyltransferase (beta4GalT) family. Family members encode type II membrane-bound glycoproteins that appear to have exclusive specificity for the donor substrate UDP-galactose. Each beta4GalT member has a distinct function in the biosynthesis of different glycoconjugates and saccharide structures. As type II membrane proteins, they have an N-terminal hydrophobic signal sequence that directs the protein to the Golgi apparatus which then remains uncleaved to function as a transmembrane anchor. The enzyme encoded by this gene attaches the first galactose in the common carbohydrate-protein linkage (GlcA-beta1,3-Gal-beta1,3-Gal-beta1,4-Xyl-beta1-O-Ser) found in proteoglycans. This enzyme differs from other beta4GalTs because it lacks the conserved Cys residues found in beta4GalT1-beta4GalT6 and it is located in cis-Golgi instead of trans-Golgi. Mutations in this gene have been associated with the progeroid form of Ehlers-Danlos syndrome. [provided by RefSeq, Oct 2009]

B4GALT7 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 7 ACMG points.

PVS1

Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant located near the start codon (<100nt), not predicted to undergo nonsense mediated mRNA decay. There are 13 pathogenic variants in the truncated region.

PM2

Very rare variant in population databases, with high coverage;

PP5

Variant 5-177600248-G-A is Pathogenic according to our data. Variant chr5-177600248-G-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 282261.We mark this variant Likely_pathogenic, oryginal submissions are: {Likely_pathogenic=2, Uncertain_significance=3, Pathogenic=2}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein
B4GALT7	NM_007255.3 linkuse as main transcript	c.38G>A	p.Trp13Ter	stop_gained	1/6	ENST00000029410.10	NP_009186.1
B4GALT7	XM_047416681.1 linkuse as main transcript	c.-1073G>A		5_prime_UTR_variant	1/7		XP_047272637.1
B4GALT7	XM_047416682.1 linkuse as main transcript	c.-358G>A		5_prime_UTR_variant	1/7		XP_047272638.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
B4GALT7	ENST00000029410.10 linkuse as main transcript	c.38G>A	p.Trp13Ter	stop_gained	1/6	1	NM_007255.3	ENSP00000029410	P1

Frequencies

GnomAD3 genomes

AF:

0.000256

AC:

AN:

152080

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.000290

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.0000654

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:

0.000383

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.000209

AC:

AN:

62262

Hom.:

AF XY:

0.000191

AC XY:

AN XY:

36736

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:

0.000544

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.000663

AC:

817

AN:

1233122

Hom.:

Cov.:

AF XY:

0.000622

AC XY:

375

AN XY:

602812

show subpopulations

Gnomad4 AFR exome

AF:

0.0000395

Gnomad4 AMR exome

AF:

0.0000476

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:

0.000793

Gnomad4 OTH exome

AF:

0.000481

GnomAD4 genome

AF:

0.000256

AC:

AN:

152080

Hom.:

Cov.:

AF XY:

0.000229

AC XY:

AN XY:

74274

show subpopulations

Gnomad4 AFR

AF:

0.000290

Gnomad4 AMR

AF:

0.0000654

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.000383

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.000401

Hom.:

Bravo

AF:

0.000280

ExAC

AF:

0.000161

AC:

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:4Uncertain:3

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

not provided

Pathogenic:2Uncertain:1

Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Apr 11, 2024	Has not been previously reported in association with a B4GALT7-related disorder to our knowledge; Nonsense variant predicted to result in protein truncation or nonsense mediated decay in a gene for which loss of function is a known mechanism of disease; This variant is associated with the following publications: (PMID: 31345219) -
Likely pathogenic, criteria provided, single submitter	clinical testing	Eurofins Ntd Llc (ga)	Aug 14, 2015	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Mayo Clinic Laboratories, Mayo Clinic	Jun 22, 2023	PVS1 -

Ehlers-Danlos syndrome, spondylodysplastic type, 1

Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Victorian Clinical Genetics Services, Murdoch Childrens Research Institute	Feb 02, 2022	Based on the classification scheme VCGS_Germline_v1.3.4, this variant is classified as Pathogenic. Following criteria are met: 0102 - Loss of function is a known mechanism of disease in this gene and is associated with Ehlers-Danlos syndrome, spondylodysplastic type, 1 (MIM#130070) (PMID: 31278392). (I) 0106 - This gene is associated with autosomal recessive disease. (I) 0201 - Variant is predicted to cause nonsense-mediated decay (NMD) and loss of protein (premature termination codon is located at least 54 nucleotides upstream of the final exon-exon junction). (SP) 0251 - This variant is heterozygous. (I) 0304 - Variant is present in gnomAD (v3) <0.01 for a recessive condition (39 heterozygotes, 0 homozygotes). (SP) 0703 - Other NMD-predicted variants comparable to the one identified in this case have moderate previous evidence for pathogenicity. These two variants have been reported as likely pathogenic, and have been reported in several patients with spondodylodysplastic-Ehlers-Danlos syndrome (EDS) (PMID: 31614862, ClinVar, Decipher). (SP) 0808 - Previous reports of pathogenicity for this variant are conflicting. This variant has been reported as both likely pathogenic and as a VUS (ClinVar and NTD Genetics). It has also been observed as homozygous in an individual with global developmental delay, broad-based gait and stereotypy, but subsequently classified as benign with no other information provided (DECIPHER). (I) 0905 - No published segregation evidence has been identified for this variant. (I) 1007 - No published functional evidence has been identified for this variant. (I) 1208 - Inheritance information for this variant is not currently available in this individual. (I) Legend: (SP) - Supporting pathogenic, (I) - Information, (SB) - Supporting benign -
Likely pathogenic, criteria provided, single submitter	research	HudsonAlpha Institute for Biotechnology, HudsonAlpha Institute for Biotechnology	Nov 13, 2023	- -

Ehlers-Danlos syndrome progeroid type

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Aug 21, 2022

This sequence change creates a premature translational stop signal (p.Trp13*) in the B4GALT7 gene. It is expected to result in an absent or disrupted protein product. However, the current clinical and genetic evidence is not sufficient to establish whether loss-of-function variants in B4GALT7 cause disease. This variant is present in population databases (rs200503833, gnomAD 0.04%). This variant has not been reported in the literature in individuals affected with B4GALT7-related conditions. ClinVar contains an entry for this variant (Variation ID: 282261). 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. -

Ehlers-Danlos syndrome

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Genome Diagnostics Laboratory, The Hospital for Sick Children

Dec 01, 2019

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_addAF

Pathogenic

0.36

BayesDel_noAF

Pathogenic

0.42

CADD

Pathogenic

DANN

Uncertain

0.99

Eigen

Pathogenic

0.88

Eigen_PC

Pathogenic

0.69

FATHMM_MKL

Benign

0.49

MutationTaster

Benign

1.0

Vest4

0.079

GERP RS

4.1

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.6

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