9-34647879-T-A

Position:

chr9-34647879-T-A

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PM1PM2PM5PP3_StrongPP5_Very_Strong

The NM_000155.4(GALT):c.425T>A(p.Met142Lys) variant causes a missense change. The variant allele was found at a frequency of 0.0000155 in 1,614,190 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. M142V) has been classified as Likely pathogenic.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000016 ( 0 hom. )

Consequence

GALT
NM_000155.4 missense

Scores

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:11

Conservation

PhyloP100: 7.10

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:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 18 ACMG points.

PM1

In a hotspot region, there are 7 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 4 uncertain in NM_000155.4

PM2

Very rare variant in population databases, with high coverage;

PM5

Other missense variant is known to change same aminoacid residue: Variant chr9-34647878-A-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 2573375.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

PP3

MetaRNN computational evidence supports a deleterious effect, 0.991

PP5

Variant 9-34647879-T-A is Pathogenic according to our data. Variant chr9-34647879-T-A is described in ClinVar as [Pathogenic]. Clinvar id is 3609.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
GALT	NM_000155.4 linkuse as main transcript	c.425T>A	p.Met142Lys	missense_variant	5/11	ENST00000378842.8
GALT	NM_001258332.2 linkuse as main transcript	c.98T>A	p.Met33Lys	missense_variant	3/9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
GALT	ENST00000378842.8 linkuse as main transcript	c.425T>A	p.Met142Lys	missense_variant	5/11	1	NM_000155.4	P1	P07902-1

Frequencies

GnomAD3 genomes

AF:

0.0000131

AC:

AN:

152180

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:

0.0000294

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000199

AC:

AN:

251496

Hom.:

AF XY:

0.0000221

AC XY:

AN XY:

135922

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:

0.0000439

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000157

AC:

AN:

1461892

Hom.:

Cov.:

AF XY:

0.0000179

AC XY:

AN XY:

727246

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:

0.0000198

Gnomad4 OTH exome

AF:

0.0000166

GnomAD4 genome

AF:

0.0000131

AC:

AN:

152298

Hom.:

Cov.:

AF XY:

0.0000134

AC XY:

AN XY:

74478

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:

0.0000294

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000282

Hom.:

Bravo

AF:

0.0000302

ExAC

AF:

0.0000412

AC:

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:11

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Deficiency of UDPglucose-hexose-1-phosphate uridylyltransferase

Pathogenic:6

Pathogenic, criteria provided, single submitter	clinical testing	Fulgent Genetics, Fulgent Genetics	Dec 02, 2021	- -
Pathogenic, criteria provided, single submitter	clinical testing	Counsyl	Mar 16, 2017	- -
Pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jul 29, 2023	This sequence change replaces methionine, which is neutral and non-polar, with lysine, which is basic and polar, at codon 142 of the GALT protein (p.Met142Lys). This variant is present in population databases (rs111033695, gnomAD 0.004%). This missense change has been observed in individual(s) with galactosemia (PMID: 2011574, 10384398, 10960497, 17041746, 20213376, 22944367, 23924834). ClinVar contains an entry for this variant (Variation ID: 3609). 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. For these reasons, this variant has been classified as Pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	Baylor Genetics	-	- -
Pathogenic, no assertion criteria provided	literature only	OMIM	Apr 01, 1991	- -
Pathogenic, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	Apr 23, 2021	Variant summary: GALT c.425T>A (p.Met142Lys) results in a non-conservative amino acid change located in the Galactose-1-phosphate uridyl transferase, N-terminal domain of the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 2e-05 in 251496 control chromosomes. c.425T>A has been reported in the literature in multiple individuals affected with Galactosemia, both in the homozygous and compound heterozygous state (Reichardt_1991, Shin_1999, Milankovics_2010, Seyrantepe_1999, Bosch_2005, Gort_2006, Boutron_2012, etc). The variant has been reported to have <10% wild-type enzyme activity when expressed in COS cells (Reichardt_1991). Three clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. All laboratories classified the variant as pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -

not provided

Pathogenic:3

Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	May 04, 2022	Expression of M142K in COS cells was associated with a severe reduction in galactose-1-phosphate uridyltransferase (GALT) enzyme activity compared to wild type (Reichardt et al. 1991); Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 22944367, 17041746, 20008339, 10960497, 20213376, 31194252, 31980526, 34030713, 31589614, 10384398, 2011574) -
Pathogenic, criteria provided, single submitter	clinical testing	Eurofins Ntd Llc (ga)	Nov 14, 2013	- -
Pathogenic, criteria provided, single submitter	clinical testing	CeGaT Center for Human Genetics Tuebingen	May 01, 2024	GALT: PM3:Very Strong, PM1, PM2, PM5, PP3, PS3:Supporting -

GALT-related disorder

Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

PreventionGenetics, part of Exact Sciences

Aug 24, 2022

The GALT c.425T>A variant is predicted to result in the amino acid substitution p.Met142Lys. This variant has previously been reported in the homozygous state or with a second pathogenic GALT variant in multiple patients with classic galactosemia (e.g., Reichardt et al. 1991. PubMed ID 2011574; Shin et al. 1999. PubMed ID 10384398; Boutron et al. 2012, PMID 22944367). The p.Met142Lys substitution was reported to abolish GALT enzyme activity in a functional study using COS cells (Reichardt et al. 1991. PubMed ID 2011574). This variant is reported in 0.0044% of alleles in individuals of European (Non-Finnish) descent in gnomAD (http://gnomad.broadinstitute.org/variant/9-34647876-T-A). It is interpreted as a pathogenic variant but multiple independent submitters to ClinVar (https://www.ncbi.nlm.nih.gov/clinvar/variation/3609/). Taken together, we interpret this variant as pathogenic. -

Galactosemia

Pathogenic:1

Pathogenic, no assertion criteria provided

clinical testing

Natera, Inc.

Mar 17, 2017

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.91

BayesDel_addAF

Pathogenic

0.48

BayesDel_noAF

Pathogenic

0.58

CADD

Pathogenic

DANN

Uncertain

0.99

DEOGEN2

Pathogenic

0.97

.;D

Eigen

Pathogenic

0.96

Eigen_PC

Pathogenic

0.86

FATHMM_MKL

Uncertain

0.96

LIST_S2

Pathogenic

0.99

D;D

M_CAP

Pathogenic

0.73

MetaRNN

Pathogenic

0.99

D;D

MetaSVM

Pathogenic

1.0

MutationAssessor

Pathogenic

3.6

.;H

MutationTaster

Benign

1.0

D;D

PrimateAI

Uncertain

0.70

PROVEAN

Pathogenic

-5.3

D;D

REVEL

Pathogenic

0.98

Sift

Pathogenic

0.0

D;D

Sift4G

Pathogenic

0.0

D;D

Polyphen

1.0

.;D

Vest4

0.96

MutPred

0.93

.;Gain of catalytic residue at M142 (P = 0.0016);

MVP

1.0

MPC

1.4

ClinPred

0.90

GERP RS

5.3

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Varity_R

0.99

gMVP

1.0

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.17

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