14-87965622-C-T

Variant summary

Our verdict is Likely pathogenic. The variant received 8 ACMG points: 8P and 0B. PM1PM2PP2PP3_ModeratePP5

The NM_000153.4(GALC):​c.916G>A​(p.Ala306Thr) variant causes a missense change. The variant allele was found at a frequency of 0.00000124 in 1,612,794 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). Synonymous variant affecting the same amino acid position (i.e. A306A) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

GALC
NM_000153.4 missense

Scores

6
8
5

Clinical Significance

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

Conservation

PhyloP100: 5.10

Publications

7 publications found
Variant links:
Genes affected
GALC (HGNC:4115): (galactosylceramidase) This gene encodes a lysosomal protein which hydrolyzes the galactose ester bonds of galactosylceramide, galactosylsphingosine, lactosylceramide, and monogalactosyldiglyceride. Mutations in this gene have been associated with Krabbe disease, also known as globoid cell leukodystrophy. Alternate transcriptional splice variants, encoding different isoforms, have been characterized. [provided by RefSeq, Jul 2008]
GALC Gene-Disease associations (from GenCC):
  • Krabbe disease
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: G2P, Myriad Women’s Health, Laboratory for Molecular Medicine, Labcorp Genetics (formerly Invitae), PanelApp Australia, ClinGen, Genomics England PanelApp

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_pathogenic. The variant received 8 ACMG points.

PM1
In a hotspot region, there are 6 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 4 uncertain in NM_000153.4
PM2
Very rare variant in population databases, with high coverage;
PP2
Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 94 curated pathogenic missense variants (we use a threshold of 10). The gene has 16 curated benign missense variants. Gene score misZ: 0.18582 (below the threshold of 3.09). Trascript score misZ: -0.28853 (below the threshold of 3.09). GenCC associations: The gene is linked to Krabbe disease.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.917
PP5
Variant 14-87965622-C-T is Pathogenic according to our data. Variant chr14-87965622-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 551587.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
GALCNM_000153.4 linkc.916G>A p.Ala306Thr missense_variant Exon 9 of 17 ENST00000261304.7 NP_000144.2 P54803-1A0A0A0MQV0

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
GALCENST00000261304.7 linkc.916G>A p.Ala306Thr missense_variant Exon 9 of 17 1 NM_000153.4 ENSP00000261304.2 P54803-1

Frequencies

GnomAD3 genomes
AF:
0.00000658
AC:
1
AN:
151938
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000242
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
GnomAD2 exomes
AF:
0.00000402
AC:
1
AN:
248764
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:
0.0000556
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
6.85e-7
AC:
1
AN:
1460856
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
726728
show subpopulations
⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.00
AC:
0
AN:
33432
American (AMR)
AF:
0.00
AC:
0
AN:
44634
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26076
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39680
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86238
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53384
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5756
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1111324
Other (OTH)
AF:
0.00
AC:
0
AN:
60332
⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.375
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
AF:
0.00000658
AC:
1
AN:
151938
Hom.:
0
Cov.:
33
AF XY:
0.0000135
AC XY:
1
AN XY:
74188
show subpopulations
African (AFR)
AF:
0.0000242
AC:
1
AN:
41356
American (AMR)
AF:
0.00
AC:
0
AN:
15232
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5186
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4826
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10552
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
314
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68012
Other (OTH)
AF:
0.00
AC:
0
AN:
2084
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.00000378

ClinVar

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

Submissions by phenotype

Galactosylceramide beta-galactosidase deficiency Pathogenic:1Uncertain:2
Jan 04, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces alanine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 306 of the GALC protein (p.Ala306Thr). This variant is present in population databases (no rsID available, gnomAD 0.006%). This missense change has been observed in individual(s) with Krabbe disease (PMID: 30089515). ClinVar contains an entry for this variant (Variation ID: 551587). 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 GALC protein function with a positive predictive value of 95%. Experimental studies have shown that this missense change affects GALC function (PMID: 27638593). 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. -

Apr 19, 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. -

May 04, 2022
Mendelics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.26
BayesDel_addAF
Uncertain
0.095
D
BayesDel_noAF
Uncertain
0.070
CADD
Pathogenic
26
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.71
D;.;.;.
Eigen
Uncertain
0.68
Eigen_PC
Pathogenic
0.67
FATHMM_MKL
Uncertain
0.96
D
LIST_S2
Pathogenic
0.98
D;D;D;D
M_CAP
Pathogenic
0.32
D
MetaRNN
Pathogenic
0.92
D;D;D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Uncertain
2.9
M;.;.;.
PhyloP100
5.1
PrimateAI
Uncertain
0.56
T
PROVEAN
Benign
-1.5
N;N;N;N
REVEL
Pathogenic
0.66
Sift
Benign
0.37
T;T;T;T
Sift4G
Benign
0.13
T;D;T;D
Polyphen
1.0
D;D;D;.
Vest4
0.79
MutPred
0.71
Gain of catalytic residue at S303 (P = 0.0055);.;.;.;
MVP
1.0
MPC
0.52
ClinPred
0.96
D
GERP RS
4.8
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.1
Varity_R
0.13
gMVP
0.77
Mutation Taster
=1/99
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.030
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: rs1349064845; hg19: chr14-88431966; COSMIC: COSV54325865; COSMIC: COSV54325865; API