9-34649041-C-T

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 0P and 0B.

The NM_000155.4(GALT):​c.864C>T​(p.Asn288Asn) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000026 in 1,613,992 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.000092 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000019 ( 0 hom. )

Consequence

GALT
NM_000155.4 synonymous

Scores

2

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:7

Conservation

PhyloP100: -0.186

Publications

2 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: Uncertain_significance. The variant received 0 ACMG points.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
GALTNM_000155.4 linkc.864C>T p.Asn288Asn synonymous_variant Exon 9 of 11 ENST00000378842.8 NP_000146.2 P07902-1B2RAT6A0A0S2Z3Y7
GALTNM_001258332.2 linkc.537C>T p.Asn179Asn synonymous_variant Exon 7 of 9 NP_001245261.1 P07902-2B2RAT6

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
GALTENST00000378842.8 linkc.864C>T p.Asn288Asn synonymous_variant Exon 9 of 11 1 NM_000155.4 ENSP00000368119.4 P07902-1
ENSG00000258728ENST00000556278.1 linkc.432+585C>T intron_variant Intron 4 of 7 5 ENSP00000451792.1 G3V4G9

Frequencies

GnomAD3 genomes
AF:
0.0000920
AC:
14
AN:
152118
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.000290
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000655
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:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000437
AC:
11
AN:
251492
AF XY:
0.0000441
show subpopulations
Gnomad AFR exome
AF:
0.000431
Gnomad AMR exome
AF:
0.0000578
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:
0.0000192
AC:
28
AN:
1461874
Hom.:
0
Cov.:
32
AF XY:
0.0000261
AC XY:
19
AN XY:
727232
show subpopulations
African (AFR)
AF:
0.000179
AC:
6
AN:
33480
American (AMR)
AF:
0.0000447
AC:
2
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26124
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.0000696
AC:
6
AN:
86258
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:
0.0000117
AC:
13
AN:
1112006
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60394
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.473
Heterozygous variant carriers
0
3
5
8
10
13
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
AF:
0.0000920
AC:
14
AN:
152118
Hom.:
0
Cov.:
32
AF XY:
0.000108
AC XY:
8
AN XY:
74306
show subpopulations
African (AFR)
AF:
0.000290
AC:
12
AN:
41416
American (AMR)
AF:
0.0000655
AC:
1
AN:
15270
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3456
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5192
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4826
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10620
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68020
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.493
Heterozygous variant carriers
0
1
2
3
4
5
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome 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
Alfa
AF:
0.000122
Hom.:
0
Bravo
AF:
0.000117

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:7
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Deficiency of UDPglucose-hexose-1-phosphate uridylyltransferase Uncertain:3
Oct 30, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change affects codon 288 of the GALT mRNA. It is a 'silent' change, meaning that it does not change the encoded amino acid sequence of the GALT protein. This variant is present in population databases (rs372134800, gnomAD 0.03%). This variant has been observed in individual(s) with features of galactosemia (PMID: 22944367). ClinVar contains an entry for this variant (Variation ID: 203732). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Jun 02, 2023
Mendelics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

May 12, 2017
Counsyl
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

This submission and the accompanying classification are no longer maintained by the submitter. For more information on current observations and classification, please contact variantquestions@myriad.com. -

not specified Uncertain:2
Feb 14, 2017
ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Feb 27, 2025
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.864C>T alters a conserved nucleotide resulting in a synonymous change. Several computational tools predict a significant impact on normal splicing: One predict the variant strengthens a cryptic 3' acceptor site. However, these predictions have yet to be confirmed by functional studies. The variant allele was found at a frequency of 4.4e-05 in 251692 control chromosomes. This frequency is not significantly higher than estimated for a pathogenic variant in GALT causing Galactosemia (4.4e-05 vs 0.0029), allowing no conclusion about variant significance. The variant, c.864C>T, has been reported in the literature in two compound heterozygous individuals affected with Galactosemia (McDonald_2009, Boutron_2012). One of these reports also noted that the diagnosis was confirmed by absent GALT activity in erythrocytes in all their cases, though no patient specific data were provided (Boutron 2012). The variant has also been reported in homozygosity in a sample from an individual that had only a residual GALT activity; and although no information was provided on the patient's phenotype, the measured enzyme activity was specific for galactosemia (Yuzyuk_2018). A conference abstract (McDonald 2009) described that cDNA containing the variant of interest (from a proband and probands father) was void of exon 9, although they both had additional variants leading to a complex haplotype (N288N, T292T and H315H) and it is not clear if the exon skipping effect was caused solely by our variant of interest or a combination effect due to this specific haplotype. These data indicate that the variant may be associated with disease. The following publications have been ascertained in the context of this evaluation (PMID: 22944367, 33636947). ClinVar contains an entry for this variant (Variation ID: 203732). Based on the evidence outlined above, the variant was classified as VUS-possibly pathogenic. -

Galactosemia Uncertain:1
Sep 16, 2020
Natera, Inc.
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

not provided Uncertain:1
Aug 30, 2021
Mayo Clinic Laboratories, Mayo Clinic
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.47
CADD
Benign
2.1
DANN
Benign
0.71
PhyloP100
-0.19
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Mutation Taster
=97/3
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.22
Details are displayed if max score is > 0.2
DS_DL_spliceai
0.22
Position offset: 40

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

Other links and lift over

dbSNP: rs372134800; hg19: chr9-34649038; API