rs758430398

Variant summary

Our verdict is Likely pathogenic. Variant got 7 ACMG points: 7P and 0B. PM2PM5PP3_ModeratePP5

The NM_000155.4(GALT):​c.200G>A​(p.Arg67His) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000496 in 1,614,026 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. R67C) has been classified as Pathogenic.

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000027 ( 0 hom. )

Consequence

GALT
NM_000155.4 missense

Scores

8
5
6

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:5U:2

Conservation

PhyloP100: 7.39
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 Likely_pathogenic. Variant got 7 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr9-34647205-C-T is described in Lovd as [Pathogenic].
PP3
MetaRNN computational evidence supports a deleterious effect, 0.887
PP5
Variant 9-34647206-G-A is Pathogenic according to our data. Variant chr9-34647206-G-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 203733.We mark this variant Likely_pathogenic, oryginal submissions are: {Likely_pathogenic=2, Uncertain_significance=2, Pathogenic=2}.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
GALTNM_000155.4 linkc.200G>A p.Arg67His missense_variant Exon 2 of 11 ENST00000378842.8 NP_000146.2 P07902-1B2RAT6A0A0S2Z3Y7
GALTNM_001258332.2 linkc.-3G>A 5_prime_UTR_variant Exon 2 of 9 NP_001245261.1 P07902-2B2RAT6

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
GALTENST00000378842.8 linkc.200G>A p.Arg67His missense_variant Exon 2 of 11 1 NM_000155.4 ENSP00000368119.4 P07902-1
ENSG00000258728ENST00000556278.1 linkc.200G>A p.Arg67His missense_variant Exon 2 of 8 5 ENSP00000451792.1 G3V4G9

Frequencies

GnomAD3 genomes
AF:
0.0000263
AC:
4
AN:
152180
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000965
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:
0.00000398
AC:
1
AN:
251342
Hom.:
0
AF XY:
0.00
AC XY:
0
AN XY:
135840
show subpopulations
Gnomad AFR exome
AF:
0.0000615
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:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000274
AC:
4
AN:
1461846
Hom.:
0
Cov.:
32
AF XY:
0.00000275
AC XY:
2
AN XY:
727214
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:
0.00000360
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.0000263
AC:
4
AN:
152180
Hom.:
0
Cov.:
32
AF XY:
0.0000269
AC XY:
2
AN XY:
74342
show subpopulations
Gnomad4 AFR
AF:
0.0000965
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
Alfa
AF:
0.0000659
Hom.:
0
Bravo
AF:
0.0000113
ExAC
AF:
0.00000824
AC:
1

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:5Uncertain:2
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Deficiency of UDPglucose-hexose-1-phosphate uridylyltransferase Pathogenic:4Uncertain:1
Nov 08, 2017
Counsyl
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Mar 17, 2024
Genomic Medicine Center of Excellence, King Faisal Specialist Hospital and Research Centre
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: research

- -

Mar 12, 2024
Baylor Genetics
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Apr 01, 2023
Clinical Laboratory Sciences Program (CLSP), King Saud bin Abdulaziz University for Health Sciences (KSAU-HS)
Significance: Likely pathogenic
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

Sep 21, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This sequence change replaces arginine, which is basic and polar, with histidine, which is basic and polar, at codon 67 of the GALT protein (p.Arg67His). This variant is present in population databases (rs758430398, gnomAD 0.008%). This missense change has been observed in individual(s) with galactosemia (PMID: 22944367). ClinVar contains an entry for this variant (Variation ID: 203733). 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. This variant disrupts the p.Arg67 amino acid residue in GALT. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 8598637, 11152465, 22944367). 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 Pathogenic:1
Aug 05, 2024
Mayo Clinic Laboratories, Mayo Clinic
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

PP3_moderate, PM2, PM3, PM5 -

not specified Uncertain:1
May 18, 2023
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Variant summary: GALT c.200G>A (p.Arg67His) results in a non-conservative amino acid change located in the Galactose-1-phosphate uridyl transferase, N-terminal (IPR005849) of the encoded protein sequence. Four of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 4e-06 in 251342 control chromosomes. c.200G>A has been reported in the literature in individuals affected with Galactosemia (Boutron_2012) and a pediatric patient with cataract (Patel_2017). To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. The following publications have been ascertained in the context of this evaluation (PMID: 22944367, 27878435). Two clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014. One laboratory classified the variant as pathogenic, and one laboratory classified the variant as uncertain significance. Based on the evidence outlined above, the variant was classified as VUS-possibly pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.15
BayesDel_addAF
Pathogenic
0.33
D
BayesDel_noAF
Pathogenic
0.41
CADD
Pathogenic
29
DANN
Pathogenic
1.0
DEOGEN2
Uncertain
0.75
D;.
Eigen
Pathogenic
0.75
Eigen_PC
Pathogenic
0.76
FATHMM_MKL
Uncertain
0.96
D
LIST_S2
Uncertain
0.91
D;D
M_CAP
Uncertain
0.26
D
MetaRNN
Pathogenic
0.89
D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Benign
1.8
L;.
PrimateAI
Uncertain
0.51
T
PROVEAN
Benign
-2.0
N;N
REVEL
Pathogenic
0.90
Sift
Benign
0.047
D;D
Sift4G
Benign
0.082
T;D
Polyphen
1.0
D;.
Vest4
0.84
MVP
0.99
MPC
2.0
ClinPred
0.94
D
GERP RS
5.5
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.1
Varity_R
0.53
gMVP
0.84

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: rs758430398; hg19: chr9-34647203; COSMIC: COSV66592761; COSMIC: COSV66592761; API