rs111033794

Variant summary

Our verdict is Pathogenic. Variant got 16 ACMG points: 16P and 0B. PM1PM2PP3_StrongPP5_Very_Strong

The NM_000155.4(GALT):​c.974C>T​(p.Pro325Leu) variant causes a missense change. The variant allele was found at a frequency of 0.00000496 in 1,614,042 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 (★★). Synonymous variant affecting the same amino acid position (i.e. P325P) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 31)
Exomes 𝑓: 0.0000048 ( 0 hom. )

Consequence

GALT
NM_000155.4 missense

Scores

16
2
1

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:8

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 16 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, 4 uncertain in NM_000155.4
PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.988
PP5
Variant 9-34649479-C-T is Pathogenic according to our data. Variant chr9-34649479-C-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 25305.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE UniProt
GALTNM_000155.4 linkuse as main transcriptc.974C>T p.Pro325Leu missense_variant 10/11 ENST00000378842.8
GALTNM_001258332.2 linkuse as main transcriptc.647C>T p.Pro216Leu missense_variant 8/9

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Appris UniProt
GALTENST00000378842.8 linkuse as main transcriptc.974C>T p.Pro325Leu missense_variant 10/111 NM_000155.4 P1P07902-1

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152174
Hom.:
0
Cov.:
31
show subpopulations
Gnomad AFR
AF:
0.0000241
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:
0.00
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000119
AC:
3
AN:
251468
Hom.:
0
AF XY:
0.00000736
AC XY:
1
AN XY:
135910
show subpopulations
Gnomad AFR exome
AF:
0.0000615
Gnomad AMR exome
AF:
0.0000289
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.0000544
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000479
AC:
7
AN:
1461868
Hom.:
0
Cov.:
31
AF XY:
0.00000413
AC XY:
3
AN XY:
727238
show subpopulations
Gnomad4 AFR exome
AF:
0.0000597
Gnomad4 AMR exome
AF:
0.0000224
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.0000504
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00000180
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152174
Hom.:
0
Cov.:
31
AF XY:
0.0000134
AC XY:
1
AN XY:
74354
show subpopulations
Gnomad4 AFR
AF:
0.0000241
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:
0.00
Gnomad4 OTH
AF:
0.00
Bravo
AF:
0.00000756
ExAC
AF:
0.00000824
AC:
1

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:8
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Deficiency of UDPglucose-hexose-1-phosphate uridylyltransferase Pathogenic:5
Pathogenic, criteria provided, single submitterclinical testingRevvity Omics, RevvitySep 19, 2020- -
Pathogenic, criteria provided, single submitterclinical testingInvitaeJan 22, 2024This sequence change replaces proline, which is neutral and non-polar, with leucine, which is neutral and non-polar, at codon 325 of the GALT protein (p.Pro325Leu). This variant is present in population databases (rs111033794, gnomAD 0.008%). This missense change has been observed in individual(s) with galactosemia (PMID: 9222760, 10573007, 20008339, 20213376, 22944367). 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: 25305). 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%. Experimental studies have shown that this missense change affects GALT function (PMID: 10573007). For these reasons, this variant has been classified as Pathogenic. -
Likely pathogenic, criteria provided, single submitterclinical testingBaylor GeneticsSep 30, 2023- -
Pathogenic, criteria provided, single submitterclinical testingWomen's Health and Genetics/Laboratory Corporation of America, LabCorpMay 23, 2022Variant summary: GALT c.974C>T (p.Pro325Leu) results in a non-conservative amino acid change located in the C-terminal domain (IPR005850) 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 1.2e-05 in 251468 control chromosomes (gnomAD). c.974C>T has been reported in the literature in homozygous- and compound heterozygous state in multiple individuals affected with Galactosemia (e.g. Greber-Platzer_1997, Hirokawa_1999, Gort_2006, Milankovics_2010, Li_2020). These data indicate that the variant is very likely to be associated with disease. At least one publication reported experimental evidence evaluating an impact on protein function and demonstrated reduced GALT activity (~11% compared to the WT control) in a cell line transfected with the variant (Hirokawa_1999). Five other 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. -
Likely pathogenic, criteria provided, single submitterclinical testingCounsylMar 22, 2018- -
not provided Pathogenic:2
Pathogenic, criteria provided, single submitterclinical testingMayo Clinic Laboratories, Mayo ClinicJan 25, 2023PP3, PP4, PM2, PS3, PS4_moderate -
Pathogenic, criteria provided, single submitterclinical testingCeGaT Center for Human Genetics TuebingenOct 01, 2019- -
Galactosemia Pathogenic:1
Pathogenic, no assertion criteria providedclinical testingNatera, Inc.Nov 29, 2017- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.88
BayesDel_addAF
Pathogenic
0.43
D
BayesDel_noAF
Pathogenic
0.55
CADD
Pathogenic
31
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.97
.;D
Eigen
Pathogenic
0.87
Eigen_PC
Pathogenic
0.82
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Pathogenic
0.99
D;D
M_CAP
Pathogenic
0.55
D
MetaRNN
Pathogenic
0.99
D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Pathogenic
3.9
.;H
MutationTaster
Benign
1.0
D;D
PrimateAI
Uncertain
0.76
T
PROVEAN
Pathogenic
-9.8
D;D
REVEL
Pathogenic
0.97
Sift
Pathogenic
0.0
D;D
Sift4G
Pathogenic
0.0
D;D
Polyphen
1.0
.;D
Vest4
0.80
MutPred
0.94
.;Loss of catalytic residue at P324 (P = 0.0318);
MVP
0.99
MPC
0.33
ClinPred
1.0
D
GERP RS
5.3
Varity_R
0.99
gMVP
0.88

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.

Other links and lift over

dbSNP: rs111033794; hg19: chr9-34649476; API