NM_000155.4:c.997C>G

Variant names:

Variant summary

Our verdict is Pathogenic. Variant got 16 ACMG points: 16P and 0B. PM2PM5PP3_StrongPP5_Very_Strong

The NM_000155.4(GALT):c.997C>G(p.Arg333Gly) variant causes a missense change. The variant allele was found at a frequency of 0.00000991 in 1,614,048 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 Pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R333L) has been classified as Likely pathogenic.

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 31)

Exomes 𝑓: 0.0000089 ( 0 hom. )

Consequence

GALT
NM_000155.4 missense

Scores

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:5

Conservation

PhyloP100: 4.13

Variant links:

Genes affected

GALT (HGNC:4135): (galactose-1-phosphate uridylyltransferase) Galactose-1-phosphate uridyl transferase (GALT) catalyzes the second step of the Leloir pathway of galactose metabolism, namely the conversion of UDP-glucose + galactose-1-phosphate to glucose-1-phosphate + UDP-galactose. The absence of this enzyme results in classic galactosemia in humans and can be fatal in the newborn period if lactose is not removed from the diet. The pathophysiology of galactosemia has not been clearly defined. Two transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Apr 2012]

GALT links:

ENSG00000258728 (HGNC:):

ENSG00000258728 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 16 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

PM5

Other missense variant is known to change same aminoacid residue: Variant chrnull-null-null-null is described in UniProt as null.

PP3

MetaRNN computational evidence supports a deleterious effect, 0.99

PP5

Variant 9-34649502-C-G is Pathogenic according to our data. Variant chr9-34649502-C-G is described in ClinVar as [Pathogenic]. Clinvar id is 3623.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
GALT	NM_000155.4 link	c.997C>G	p.Arg333Gly	missense_variant	Exon 10 of 11	ENST00000378842.8	NP_000146.2	P07902-1B2RAT6A0A0S2Z3Y7
GALT	NM_001258332.2 link	c.670C>G	p.Arg224Gly	missense_variant	Exon 8 of 9		NP_001245261.1	P07902-2B2RAT6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
GALT	ENST00000378842.8 link	c.997C>G	p.Arg333Gly	missense_variant	Exon 10 of 11	1	NM_000155.4	ENSP00000368119.4		P07902-1
ENSG00000258728	ENST00000556278.1 link	c.432+1046C>G		intron_variant	Intron 4 of 7	5		ENSP00000451792.1		G3V4G9

Frequencies

GnomAD3 genomes

AF:

0.0000197

AC:

AN:

152172

Hom.:

Cov.:

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:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000441

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.00000398

AC:

AN:

251474

Hom.:

AF XY:

0.00000736

AC XY:

AN XY:

135916

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:

0.00000879

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000889

AC:

AN:

1461876

Hom.:

Cov.:

AF XY:

0.00000825

AC XY:

AN XY:

727240

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:

0.0000108

Gnomad4 OTH exome

AF:

0.0000166

GnomAD4 genome

AF:

0.0000197

AC:

AN:

152172

Hom.:

Cov.:

AF XY:

0.0000134

AC XY:

AN XY:

74352

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000441

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.00000756

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:5

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Deficiency of UDPglucose-hexose-1-phosphate uridylyltransferase

Pathogenic:4

Aug 11, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Experimental studies have shown that this missense change affects GALT function (PMID: 23583749). This variant disrupts the p.Arg333 amino acid residue in GALT. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 1897530, 10384398, 10399107, 18207281, 25592817). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. For these reasons, this variant has been classified as Pathogenic. ClinVar contains an entry for this variant (Variation ID: 3623). This sequence change replaces arginine, which is basic and polar, with glycine, which is neutral and non-polar, at codon 333 of the GALT protein (p.Arg333Gly). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with galactosemia (PMID: 10439960, 12872845, 23749220). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt GALT protein function. -

May 28, 2019

Mendelics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Jul 01, 1999

OMIM

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: literature only

- -

Feb 13, 2024

Baylor Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Galactosemia

Pathogenic:1

Mar 17, 2017

Natera, Inc.

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.78

BayesDel_addAF

Pathogenic

0.53

BayesDel_noAF

Pathogenic

0.53

CADD

Pathogenic

DANN

Uncertain

1.0

DEOGEN2

Pathogenic

0.96

.;D

Eigen

Uncertain

0.42

Eigen_PC

Uncertain

0.38

FATHMM_MKL

Pathogenic

0.98

LIST_S2

Pathogenic

0.98

D;D

M_CAP

Pathogenic

0.73

MetaRNN

Pathogenic

0.99

D;D

MetaSVM

Pathogenic

1.1

MutationAssessor

Pathogenic

3.5

.;M

PrimateAI

Uncertain

0.70

PROVEAN

Pathogenic

-5.8

D;D

REVEL

Pathogenic

0.91

Sift

Pathogenic

0.0

D;D

Sift4G

Uncertain

0.013

D;D

Polyphen

0.96

.;D

Vest4

0.94

MutPred

0.93

.;Loss of MoRF binding (P = 0.0176);

MVP

0.99

MPC

0.36

ClinPred

0.98

GERP RS

4.3

Varity_R

0.91

gMVP

0.77

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