rs111033810

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PM1PM2PM5PP2PP3_ModeratePP5

The NM_000155.4(GALT):​c.1006A>G​(p.Met336Val) variant causes a missense change. The variant allele was found at a frequency of 0.00000137 in 1,461,884 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 Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. M336L) has been classified as Likely pathogenic.

Frequency

Genomes: not found (cov: 31)
Exomes 𝑓: 0.0000014 ( 0 hom. )

Consequence

GALT
NM_000155.4 missense

Scores

10
8
1

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:2U:1

Conservation

PhyloP100: 4.84

Publications

7 publications found
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 Gene-Disease associations (from GenCC):
  • classic galactosemia
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), G2P, Orphanet
  • galactosemia
    Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen, Myriad Women’s Health

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 10 ACMG points.

PM1
In a hotspot region, there are 9 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 8 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 chr9-34649511-A-T is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 25315.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
PP2
Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 104 curated pathogenic missense variants (we use a threshold of 10). The gene has 17 curated benign missense variants. Gene score misZ: 0.91493 (below the threshold of 3.09). Trascript score misZ: 1.8645 (below the threshold of 3.09). GenCC associations: The gene is linked to galactosemia, classic galactosemia.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.912
PP5
Variant 9-34649511-A-G is Pathogenic according to our data. Variant chr9-34649511-A-G is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 280997.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
GALTNM_000155.4 linkc.1006A>G p.Met336Val missense_variant Exon 10 of 11 ENST00000378842.8 NP_000146.2 P07902-1B2RAT6A0A0S2Z3Y7
GALTNM_001258332.2 linkc.679A>G p.Met227Val 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.1006A>G p.Met336Val missense_variant Exon 10 of 11 1 NM_000155.4 ENSP00000368119.4 P07902-1
ENSG00000258728ENST00000556278.1 linkc.432+1055A>G intron_variant Intron 4 of 7 5 ENSP00000451792.1 G3V4G9

Frequencies

GnomAD3 genomes
Cov.:
31
GnomAD2 exomes
AF:
0.0000159
AC:
4
AN:
251478
AF XY:
0.00
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.000163
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000879
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000137
AC:
2
AN:
1461884
Hom.:
0
Cov.:
31
AF XY:
0.00
AC XY:
0
AN XY:
727244
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.0000504
AC:
2
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53416
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1112006
Other (OTH)
AF:
0.00
AC:
0
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.425
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
Cov.:
31
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.00000378
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.0000247
AC:
3

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:2Uncertain:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Deficiency of UDPglucose-hexose-1-phosphate uridylyltransferase Pathogenic:2
Jun 12, 2025
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: GALT c.1006A>G (p.Met336Val) results in a conservative amino acid change located in the Galactose-1-phosphate uridyl transferase, C-terminal domain (IPR005850) of the encoded protein sequence. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change. The variant allele was found at a frequency of 1.6e-05 in 251478 control chromosomes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.1006A>G has been observed in a biallelic genotype at least one individual affected with Galactosemia (Labcorp Genetics (formerly Invitae)). These data do not allow any conclusion about variant significance. Internal data demonstrated this variant was in trans with a likely pathogenic/pathogenic missense variant (c.428C>T, p.Ser143Leu) in at least 1 individual with undetectable enzyme activity in patient sample (Labcorp Genetics (formerly Invitae)). The following publications have been ascertained in the context of this evaluation (PMID: 27308838). ClinVar contains an entry for this variant (Variation ID: 280997). Based on the evidence outlined above, the variant was classified as likely pathogenic. -

Feb 09, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces methionine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 336 of the GALT protein (p.Met336Val). This variant is present in population databases (rs111033810, gnomAD 0.02%). This missense change has been observed in individual(s) with features of galactosemia (Invitae). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. ClinVar contains an entry for this variant (Variation ID: 280997). 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 with a positive predictive value of 95%. This variant disrupts the p.Met336 amino acid residue in GALT. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 11397328, 17876724). 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. -

not provided Uncertain:1
Sep 18, 2015
Eurofins Ntd Llc (ga)
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.37
BayesDel_addAF
Pathogenic
0.34
D
BayesDel_noAF
Pathogenic
0.52
CADD
Pathogenic
26
DANN
Uncertain
0.99
DEOGEN2
Pathogenic
0.91
.;D
Eigen
Uncertain
0.63
Eigen_PC
Uncertain
0.64
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Pathogenic
0.99
D;D
M_CAP
Pathogenic
0.51
D
MetaRNN
Pathogenic
0.91
D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Pathogenic
3.3
.;M
PhyloP100
4.8
PrimateAI
Uncertain
0.78
T
PROVEAN
Uncertain
-3.8
D;D
REVEL
Pathogenic
0.96
Sift
Uncertain
0.017
D;D
Sift4G
Uncertain
0.034
D;D
Polyphen
0.71
.;P
Vest4
0.82
MVP
0.99
MPC
0.33
ClinPred
0.83
D
GERP RS
5.2
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.62
gMVP
0.78
Mutation Taster
=14/86
disease causing

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

Other links and lift over

dbSNP: rs111033810; hg19: chr9-34649508; API