NM_000155.4:c.1030C>A

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PM2PP3_ModeratePP5_Very_Strong

The NM_000155.4(GALT):​c.1030C>A​(p.Gln344Lys) variant causes a missense change. The variant allele was found at a frequency of 0.00000434 in 1,614,072 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 Likely pathogenic (★★).

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 31)
Exomes 𝑓: 0.0000021 ( 0 hom. )

Consequence

GALT
NM_000155.4 missense

Scores

12
6
1

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:11

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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 12 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.912
PP5
Variant 9-34649535-C-A is Pathogenic according to our data. Variant chr9-34649535-C-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 25320.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
GALTNM_000155.4 linkc.1030C>A p.Gln344Lys missense_variant Exon 10 of 11 ENST00000378842.8 NP_000146.2 P07902-1B2RAT6A0A0S2Z3Y7
GALTNM_001258332.2 linkc.703C>A p.Gln235Lys missense_variant Exon 8 of 9 NP_001245261.1 P07902-2B2RAT6

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
GALTENST00000378842.8 linkc.1030C>A p.Gln344Lys missense_variant Exon 10 of 11 1 NM_000155.4 ENSP00000368119.4 P07902-1
ENSG00000258728ENST00000556278.1 linkc.432+1079C>A intron_variant Intron 4 of 7 5 ENSP00000451792.1 G3V4G9

Frequencies

GnomAD3 genomes
AF:
0.0000263
AC:
4
AN:
152198
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:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000588
Gnomad OTH
AF:
0.00
GnomAD4 exome
AF:
0.00000205
AC:
3
AN:
1461874
Hom.:
0
Cov.:
31
AF XY:
0.00000138
AC XY:
1
AN XY:
727238
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:
0.00000270
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.0000263
AC:
4
AN:
152198
Hom.:
0
Cov.:
31
AF XY:
0.0000403
AC XY:
3
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:
0.0000588
Gnomad4 OTH
AF:
0.00
Bravo
AF:
0.00000378
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000116
AC:
1

ClinVar

Significance: Pathogenic/Likely 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:7
Jun 19, 2023
ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The GALT c.1030C>A; p.Gln344Lys variant (rs111033814) has been reported in patients diagnosed with hereditary galactosemia (Elsas 1998, Berry 2000, Yang 2002). This variant is also reported in ClinVar (Variation ID: 25320). It is only found on two alleles in the Genome Aggregation Database, indicating it is not a common polymorphism. Codon 344 is located at the subunit interface and is predicted to be important for maintaining inter-subunit hydrogen bonds and stabilize the enzyme complex (Facchiano 2010). Functional characterization indicates that, when found in trans with another pathogenic GALT variant, the p.Gln344Lys variant abrogates GALT activity in erythrocytes (Berry 2000). Based on available information, this variant is considered to be pathogenic. References: Berry G et al. Galactose breath testing distinguishes variant and severe galactose-1-phosphate uridyltransferase genotypes. Pediatr Res. 2000; 48(3):323-8. PMID: 10960497. Elsas LJ et al. The molecular biology of galactosemia. Genet Med. 1998; 1(1):40-8. PMID: 11261429. Facchiano A et al. Analysis of galactosemia-linked mutations of GALT enzyme using a computational biology approach. Protein Eng Des Sel. 2010; 23(2):103-13. PMID: 20008339. Yang Y et al. Molecular analysis in newborns from Texas affected with galactosemia. Hum Mutat. 2002; 19(1):82-3. PMID: 11754113. -

Jun 22, 2022
Revvity Omics, Revvity
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Feb 21, 2024
Fulgent Genetics, Fulgent Genetics
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

-
Baylor Genetics
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Nov 03, 2021
Myriad Genetics, Inc.
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

NM_000155.3(GALT):c.1030C>A(Q344K) is a missense variant classified as likely pathogenic in the context of galactosemia. Q344K has been observed in cases with relevant disease (PMID: 27363831, 21779791, 14728988, 11754113, Dobrowlski_2017_(no PMID; abstract)). Functional assessments of this variant are available in the literature (PMID: 23319291). Q344K has been observed in population frequency databases (gnomAD: NFE 0.01%). In summary, NM_000155.3(GALT):c.1030C>A(Q344K) is a missense variant that has been observed more frequently in cases with the relevant disease than in healthy populations. Please note: this variant was assessed in the context of healthy population screening. -

Jan 29, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This sequence change replaces glutamine, which is neutral and polar, with lysine, which is basic and polar, at codon 344 of the GALT protein (p.Gln344Lys). This variant is present in population databases (rs111033814, gnomAD 0.01%). This missense change has been observed in individual(s) with galactosemia (PMID: 11397328, 11754113; internal data). ClinVar contains an entry for this variant (Variation ID: 25320). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is expected to disrupt GALT protein function with a positive predictive value of 80%. Experimental studies have shown that this missense change affects GALT function (PMID: 23319291). For these reasons, this variant has been classified as Pathogenic. -

Mar 14, 2022
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Variant summary: GALT c.1030C>A (p.Gln344Lys) results in a conservative amino acid change located in the Galactose-1-phosphate uridyl transferase, C-terminal domain of the encoded protein sequence. Four of five in-silico tools predict a damaging effect of the variant on protein function. The variant was absent in 251468 control chromosomes. c.1030C>A has been reported in the literature in individuals affected with Galactosemia. These data indicate that the variant is likely to be associated with disease. At least one publication reports experimental evidence evaluating an impact on protein function. The most pronounced variant effect results in <10% of normal activity. Six 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/likely pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -

not provided Pathogenic:4
Jan 21, 2025
GeneDx
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Published functional studies demonstrate a loss of enzyme activity (PMID: 23319291); 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: 25087612, 10408771, 11261429, 11754113, 14728988, 11113841, 20008339, 23319291, 11397328, 27363831, 21779791, 35677809, 10960497, Moody2023[Preprint]) -

Sep 03, 2024
Mayo Clinic Laboratories, Mayo Clinic
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

PP3, PM2_moderate -

Jul 07, 2017
Eurofins Ntd Llc (ga)
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Dec 04, 2014
Center for Pediatric Genomic Medicine, Children's Mercy Hospital and Clinics
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.66
BayesDel_addAF
Pathogenic
0.52
D
BayesDel_noAF
Pathogenic
0.51
CADD
Pathogenic
27
DANN
Uncertain
0.99
DEOGEN2
Pathogenic
0.93
.;D
Eigen
Uncertain
0.53
Eigen_PC
Uncertain
0.56
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Pathogenic
0.98
D;D
M_CAP
Pathogenic
0.62
D
MetaRNN
Pathogenic
0.91
D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Pathogenic
3.1
.;M
PrimateAI
Pathogenic
0.80
T
PROVEAN
Uncertain
-2.4
N;D
REVEL
Pathogenic
0.91
Sift
Uncertain
0.0020
D;D
Sift4G
Uncertain
0.019
D;D
Polyphen
0.87
.;P
Vest4
0.83
MVP
0.97
MPC
0.26
ClinPred
0.95
D
GERP RS
5.2
Varity_R
0.95
gMVP
0.78

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.010
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: rs111033814; hg19: chr9-34649532; API