rs111033689

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong

The NM_000155.4(GALT):​c.400delT​(p.Trp134GlyfsTer4) variant causes a frameshift change. The variant allele was found at a frequency of 0.000013 in 1,461,892 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★★). Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 0.000013 ( 0 hom. )

Consequence

GALT
NM_000155.4 frameshift

Scores

Not classified

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:4

Conservation

PhyloP100: 5.41

Publications

4 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 18 ACMG points.

PVS1
Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 9-34647853-CT-C is Pathogenic according to our data. Variant chr9-34647853-CT-C is described in ClinVar as [Pathogenic]. Clinvar id is 25171.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.400delT p.Trp134GlyfsTer4 frameshift_variant Exon 5 of 11 ENST00000378842.8 NP_000146.2 P07902-1B2RAT6A0A0S2Z3Y7
GALTNM_001258332.2 linkc.73delT p.Trp25GlyfsTer4 frameshift_variant Exon 3 of 9 NP_001245261.1 P07902-2B2RAT6

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
GALTENST00000378842.8 linkc.400delT p.Trp134GlyfsTer4 frameshift_variant Exon 5 of 11 1 NM_000155.4 ENSP00000368119.4 P07902-1
ENSG00000258728ENST00000556278.1 linkc.253-261delT intron_variant Intron 2 of 7 5 ENSP00000451792.1 G3V4G9

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD2 exomes
AF:
0.00000398
AC:
1
AN:
251494
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:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000879
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000130
AC:
19
AN:
1461892
Hom.:
0
Cov.:
33
AF XY:
0.0000138
AC XY:
10
AN XY:
727246
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:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86256
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000171
AC:
19
AN:
1112012
Other (OTH)
AF:
0.00
AC:
0
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.488
Heterozygous variant carriers
0
1
2
4
5
6
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.:
32

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:4
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Deficiency of UDPglucose-hexose-1-phosphate uridylyltransferase Pathogenic:2
Feb 01, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change creates a premature translational stop signal (p.Trp134Glyfs*4) in the GALT gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in GALT are known to be pathogenic (PMID: 22944367). This variant is not present in population databases (gnomAD no frequency). This premature translational stop signal has been observed in individual(s) with galactosemia (PMID: 25592817). ClinVar contains an entry for this variant (Variation ID: 25171). For these reasons, this variant has been classified as Pathogenic. -

Nov 08, 2023
Baylor Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Galactosemia Pathogenic:1
Dec 12, 2017
Natera, Inc.
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

not provided Pathogenic:1
Oct 11, 2017
ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The GALT c.400delT;p.Trp134fs variant is reported in the medical literature in several individuals, including individuals with classic galactosemia (Bosch 2005, Tyfield 1999, Viggiano 2015). The variant is listed in the ClinVar database (Variation ID: 25171) and in the dbSNP variant database (rs111033689) but not described in the general population-based databases (Exome Variant Server, Genome Aggregation Database). This variant deletes one nucleotide, creating a frameshift, and is predicted to result in a truncated protein or mRNA subject to non-sense mediated decay. Considering available information, this variant is classified as pathogenic. References: Bosch AM et al. Identification of novel mutations in classical galactosemia. Hum Mutat. 2005 May;25(5):502. Tyfield L et al. Classical galactosemia and mutations at the galactose-1-phosphate uridyl transferase (GALT) gene. Hum Mutat. 1999;13(6):417-30. Viggiano E et al. Clinical and molecular spectra in galactosemic patients from neonatal screening in northeastern Italy: structural and functional characterization of new variations in the galactose-1-phosphate uridyltransferase (GALT) gene. Gene. 2015 Apr 1;559(2):112-8. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
PhyloP100
5.4
Mutation Taster
=0/200
disease causing (ClinVar)

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.13
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: rs111033689; hg19: chr9-34647850; API