5-177600230-A-G

Position:

chr5-177600230-A-G

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2BP4

The NM_007255.3(B4GALT7):c.20A>G(p.Lys7Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000043 in 1,395,186 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 Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 31)

Exomes 𝑓: 0.0000032 ( 0 hom. )

Consequence

B4GALT7
NM_007255.3 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 1.94

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 Uncertain_significance. Variant got 1 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (MetaRNN=0.31902307).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
B4GALT7	NM_007255.3 link	c.20A>G	p.Lys7Arg	missense_variant	1/6	ENST00000029410.10	NP_009186.1	Q9UBV7
B4GALT7	XM_047416681.1 link	c.-1091A>G		5_prime_UTR_variant	1/7		XP_047272637.1
B4GALT7	XM_047416682.1 link	c.-376A>G		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 link	c.20A>G	p.Lys7Arg	missense_variant	1/6	1	NM_007255.3	ENSP00000029410.5		Q9UBV7

Frequencies

GnomAD3 genomes

AF:

0.0000132

AC:

AN:

151922

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.000131

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

GnomAD4 exome

AF:

0.00000322

AC:

AN:

1243264

Hom.:

Cov.:

AF XY:

0.00000328

AC XY:

AN XY:

609330

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.000130

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:

0.00000100

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000132

AC:

AN:

151922

Hom.:

Cov.:

AF XY:

0.0000270

AC XY:

AN XY:

74202

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.000131

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:

0.00

Bravo

AF:

0.0000227

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Ehlers-Danlos syndrome progeroid type

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Nov 08, 2022

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. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be tolerated. ClinVar contains an entry for this variant (Variation ID: 1391422). This variant has not been reported in the literature in individuals affected with B4GALT7-related conditions. The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. This sequence change replaces lysine, which is basic and polar, with arginine, which is basic and polar, at codon 7 of the B4GALT7 protein (p.Lys7Arg). -

Inborn genetic diseases

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Apr 13, 2022

The c.20A>G (p.K7R) alteration is located in exon 1 (coding exon 1) of the B4GALT7 gene. This alteration results from a A to G substitution at nucleotide position 20, causing the lysine (K) at amino acid position 7 to be replaced by an arginine (R). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.070

BayesDel_addAF

Benign

-0.079

BayesDel_noAF

Benign

-0.35

CADD

Benign

DANN

Uncertain

1.0

DEOGEN2

Benign

0.026

Eigen

Uncertain

0.26

Eigen_PC

Benign

0.21

FATHMM_MKL

Benign

0.74

LIST_S2

Benign

0.67

M_CAP

Pathogenic

0.36

MetaRNN

Benign

0.32

MetaSVM

Benign

-0.42

MutationAssessor

Benign

1.7

PrimateAI

Pathogenic

0.88

PROVEAN

Benign

-0.31

REVEL

Benign

0.20

Sift

Pathogenic

0.0

Sift4G

Benign

0.23

Polyphen

0.99

Vest4

0.094

MutPred

0.23

Loss of methylation at K7 (P = 0.013);

MVP

0.73

MPC

0.19

ClinPred

0.37

GERP RS

3.0

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.0

Varity_R

0.35

gMVP

0.46

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