NM_001478.5:c.514G>A

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2BP4_Strong

The NM_001478.5(B4GALNT1):​c.514G>A​(p.Gly172Ser) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000193 in 1,609,126 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 16/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G172R) has been classified as Benign.

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000019 ( 0 hom. )

Consequence

B4GALNT1
NM_001478.5 missense

Scores

19

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 0.526

Publications

11 publications found
Variant links:
Genes affected
B4GALNT1 (HGNC:4117): (beta-1,4-N-acetyl-galactosaminyltransferase 1) GM2 and GD2 gangliosides are sialic acid-containing glycosphingolipids. GalNAc-T is the enzyme involved in the biosynthesis of G(M2) and G(D2) glycosphingolipids. GalNAc-T catalyzes the transfer of GalNAc into G(M3) and G(D3) by a beta-1,4 linkage, resulting in the synthesis of G(M2) and G(D2), respectively. Three transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Feb 2013]
B4GALNT1 Gene-Disease associations (from GenCC):
  • complex hereditary spastic paraplegia
    Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
  • hereditary spastic paraplegia 26
    Inheritance: AR Classification: STRONG, MODERATE, SUPPORTIVE Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae), Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -2 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.059913218).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
B4GALNT1NM_001478.5 linkc.514G>A p.Gly172Ser missense_variant Exon 5 of 11 ENST00000341156.9 NP_001469.1 Q00973-1B4DSP5

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
B4GALNT1ENST00000341156.9 linkc.514G>A p.Gly172Ser missense_variant Exon 5 of 11 1 NM_001478.5 ENSP00000341562.4 Q00973-1

Frequencies

GnomAD3 genomes
AF:
0.0000197
AC:
3
AN:
152190
Hom.:
0
Cov.:
33
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:
0.0000294
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000811
AC:
2
AN:
246592
AF XY:
0.00000751
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:
0.0000179
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000192
AC:
28
AN:
1456936
Hom.:
0
Cov.:
32
AF XY:
0.0000193
AC XY:
14
AN XY:
724456
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33296
American (AMR)
AF:
0.00
AC:
0
AN:
43966
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25748
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39660
South Asian (SAS)
AF:
0.00
AC:
0
AN:
85414
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53244
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5718
European-Non Finnish (NFE)
AF:
0.0000252
AC:
28
AN:
1109692
Other (OTH)
AF:
0.00
AC:
0
AN:
60198
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.466
Heterozygous variant carriers
0
2
4
6
8
10
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:
0.0000197
AC:
3
AN:
152190
Hom.:
0
Cov.:
33
AF XY:
0.0000135
AC XY:
1
AN XY:
74340
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41436
American (AMR)
AF:
0.00
AC:
0
AN:
15290
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5204
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4828
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10608
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000294
AC:
2
AN:
68034
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.558
Heterozygous variant carriers
0
1
1
2
2
3
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:
0.00
Hom.:
23
Bravo
AF:
0.0000113

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Spastic paraplegia Uncertain:1
Aug 15, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

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. Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Tolerated"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0". The serine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. This variant has not been reported in the literature in individuals affected with B4GALNT1-related conditions. ClinVar contains an entry for this variant (Variation ID: 639794). This variant is present in population databases (no rsID available, gnomAD 0.002%). This sequence change replaces glycine, which is neutral and non-polar, with serine, which is neutral and polar, at codon 172 of the B4GALNT1 protein (p.Gly172Ser). -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.065
BayesDel_addAF
Benign
-0.23
T
BayesDel_noAF
Benign
-0.57
CADD
Benign
16
DANN
Benign
0.97
DEOGEN2
Benign
0.21
T;.;T;.;.;.
Eigen
Benign
-0.72
Eigen_PC
Benign
-0.65
FATHMM_MKL
Benign
0.080
N
LIST_S2
Benign
0.80
T;T;T;.;T;T
M_CAP
Benign
0.0087
T
MetaRNN
Benign
0.060
T;T;T;T;T;T
MetaSVM
Benign
-1.0
T
MutationAssessor
Benign
0.69
N;.;.;N;N;.
PhyloP100
0.53
PrimateAI
Benign
0.34
T
PROVEAN
Benign
0.39
N;N;.;N;N;N
REVEL
Benign
0.13
Sift
Benign
0.17
T;T;.;T;T;T
Sift4G
Benign
0.78
T;T;T;T;T;.
Polyphen
0.0
B;.;B;.;.;.
Vest4
0.13
MutPred
0.24
Gain of catalytic residue at Q168 (P = 0.0328);.;Gain of catalytic residue at Q168 (P = 0.0328);Gain of catalytic residue at Q168 (P = 0.0328);Gain of catalytic residue at Q168 (P = 0.0328);Gain of catalytic residue at Q168 (P = 0.0328);
MVP
0.24
MPC
0.22
ClinPred
0.76
D
GERP RS
4.5
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.0
Varity_R
0.12
gMVP
0.63
Mutation Taster
=96/4
polymorphism

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

Other links and lift over

dbSNP: rs810205; hg19: chr12-58024278; API