22-42693185-C-T

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2PP3_Strong

The NM_017436.7(A4GALT):​c.767G>A​(p.Arg256Gln) variant causes a missense change. The variant allele was found at a frequency of 0.00000125 in 1,598,240 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 Uncertain significance (★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 31)
Exomes 𝑓: 6.9e-7 ( 0 hom. )

Consequence

A4GALT
NM_017436.7 missense

Scores

6
10
3

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 3.78
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]
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.956

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE UniProt
A4GALTNM_017436.7 linkuse as main transcriptc.767G>A p.Arg256Gln missense_variant 3/3 ENST00000642412.2

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Appris UniProt
A4GALTENST00000642412.2 linkuse as main transcriptc.767G>A p.Arg256Gln missense_variant 3/3 NM_017436.7 P1

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152190
Hom.:
0
Cov.:
31
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.000193
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:
6.92e-7
AC:
1
AN:
1446050
Hom.:
0
Cov.:
66
AF XY:
0.00000139
AC XY:
1
AN XY:
718450
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
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:
9.04e-7
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152190
Hom.:
0
Cov.:
31
AF XY:
0.0000134
AC XY:
1
AN XY:
74352
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.000193
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.00
Gnomad4 OTH
AF:
0.00

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

not specified Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingAmbry GeneticsMay 26, 2023The c.767G>A (p.R256Q) alteration is located in exon 3 (coding exon 1) of the A4GALT gene. This alteration results from a G to A substitution at nucleotide position 767, causing the arginine (R) at amino acid position 256 to be replaced by a glutamine (Q). 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
Pathogenic
0.71
BayesDel_addAF
Pathogenic
0.25
D
BayesDel_noAF
Uncertain
0.12
CADD
Uncertain
25
DANN
Pathogenic
1.0
DEOGEN2
Benign
0.41
T;T;T;T
Eigen
Uncertain
0.34
Eigen_PC
Uncertain
0.31
FATHMM_MKL
Benign
0.59
D
LIST_S2
Uncertain
0.96
.;.;D;.
M_CAP
Uncertain
0.25
D
MetaRNN
Pathogenic
0.96
D;D;D;D
MetaSVM
Uncertain
0.58
D
MutationAssessor
Pathogenic
3.4
M;M;M;M
MutationTaster
Benign
0.96
D;D;D
PrimateAI
Uncertain
0.56
T
PROVEAN
Uncertain
-3.6
.;D;D;D
REVEL
Pathogenic
0.71
Sift
Uncertain
0.0020
.;D;D;D
Sift4G
Uncertain
0.011
.;D;D;D
Polyphen
0.75
P;P;P;P
Vest4
0.70, 0.71, 0.71
MutPred
0.90
Loss of MoRF binding (P = 0.0095);Loss of MoRF binding (P = 0.0095);Loss of MoRF binding (P = 0.0095);Loss of MoRF binding (P = 0.0095);
MVP
0.92
MPC
1.2
ClinPred
0.99
D
GERP RS
4.3
Varity_R
0.75
gMVP
0.77

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.020
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.

Other links and lift over

dbSNP: rs1465524001; hg19: chr22-43089191; API