chr22-42693282-C-T

Position:

chr22-42693282-C-T

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2BP4_Strong

The NM_017436.7(A4GALT):c.670G>A(p.Glu224Lys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000973 in 1,612,868 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. 16/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.000039 ( 0 hom., cov: 31)

Exomes 𝑓: 0.00010 ( 1 hom. )

Consequence

A4GALT
NM_017436.7 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 0.0870

Variant links:

Genes affected

A4GALT (HGNC:18149): (alpha 1,4-galactosyltransferase (P1PK blood group)) The protein encoded by this gene catalyzes the transfer of galactose to lactosylceramide to form globotriaosylceramide, which has been identified as the P(k) antigen of the P blood group system. This protein, a type II membrane protein found in the Golgi, is also required for the synthesis of the bacterial verotoxins receptor. Alternatively spliced transcript variants have been found for this gene. [provided by RefSeq, Dec 2015]

A4GALT links:

CYB5R3 (HGNC:2873): (cytochrome b5 reductase 3) This gene encodes cytochrome b5 reductase, which includes a membrane-bound form in somatic cells (anchored in the endoplasmic reticulum, mitochondrial and other membranes) and a soluble form in erythrocytes. The membrane-bound form exists mainly on the cytoplasmic side of the endoplasmic reticulum and functions in desaturation and elongation of fatty acids, in cholesterol biosynthesis, and in drug metabolism. The erythrocyte form is located in a soluble fraction of circulating erythrocytes and is involved in methemoglobin reduction. The membrane-bound form has both membrane-binding and catalytic domains, while the soluble form has only the catalytic domain. Alternate splicing results in multiple transcript variants. Mutations in this gene cause methemoglobinemias. [provided by RefSeq, Jan 2010]

CYB5R3 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -2 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (MetaRNN=0.043517083).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
A4GALT	NM_017436.7 linkuse as main transcript	c.670G>A	p.Glu224Lys	missense_variant	3/3	ENST00000642412.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
A4GALT	ENST00000642412.2 linkuse as main transcript	c.670G>A	p.Glu224Lys	missense_variant	3/3		NM_017436.7	P1

Frequencies

GnomAD3 genomes

AF:

0.0000394

AC:

AN:

152196

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.000576

Gnomad EAS

AF:

0.000385

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000294

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.000101

AC:

AN:

248742

Hom.:

AF XY:

0.000104

AC XY:

AN XY:

135246

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.000116

Gnomad ASJ exome

AF:

0.000702

Gnomad EAS exome

AF:

0.000491

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000447

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.000103

AC:

151

AN:

1460672

Hom.:

Cov.:

AF XY:

0.000105

AC XY:

AN XY:

726656

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.0000895

Gnomad4 ASJ exome

AF:

0.000727

Gnomad4 EAS exome

AF:

0.00189

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000396

Gnomad4 OTH exome

AF:

0.000149

GnomAD4 genome

AF:

0.0000394

AC:

AN:

152196

Hom.:

Cov.:

AF XY:

0.0000134

AC XY:

AN XY:

74370

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.000576

Gnomad4 EAS

AF:

0.000385

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000294

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000901

Hom.:

Bravo

AF:

0.0000491

ExAC

AF:

0.0000494

AC:

Asia WGS

AF:

0.000289

AC:

AN:

3478

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

not provided

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Oct 24, 2022

This sequence change replaces glutamic acid, which is acidic and polar, with lysine, which is basic and polar, at codon 224 of the A4GALT protein (p.Glu224Lys). This variant is present in population databases (rs150748224, gnomAD 0.07%), and has an allele count higher than expected for a pathogenic variant. 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 output the following: SIFT: "Not Available"; PolyPhen-2: "Benign"; Align-GVGD: "Not Available". The lysine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. This variant has not been reported in the literature in individuals affected with A4GALT-related conditions. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.11

BayesDel_addAF

Benign

-0.34

BayesDel_noAF

Benign

-0.39

CADD

Benign

5.4

DANN

Benign

0.80

DEOGEN2

Benign

0.11

T;T;T;T

Eigen

Benign

-0.94

Eigen_PC

Benign

-0.90

FATHMM_MKL

Benign

0.082

LIST_S2

Benign

0.82

.;.;T;.

M_CAP

Benign

0.025

MetaRNN

Benign

0.044

T;T;T;T

MetaSVM

Benign

-0.94

MutationAssessor

Benign

1.5

L;L;L;L

MutationTaster

Benign

0.92

N;N;N

PrimateAI

Benign

0.32

PROVEAN

Benign

-0.60

.;N;N;N

REVEL

Benign

0.094

Sift

Benign

0.85

.;T;T;T

Sift4G

Benign

0.67

.;T;T;T

Polyphen

0.040

B;B;B;B

Vest4

0.099, 0.097, 0.098

MutPred

0.64

Gain of ubiquitination at E224 (P = 0.0369);Gain of ubiquitination at E224 (P = 0.0369);Gain of ubiquitination at E224 (P = 0.0369);Gain of ubiquitination at E224 (P = 0.0369);

MVP

0.48

MPC

0.39

ClinPred

0.83

GERP RS

0.46

Varity_R

0.036

gMVP

0.78

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