rs397509426

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PM1PM2PM5PP3_StrongPP5_Very_Strong

The NM_021971.4(GMPPB):​c.95C>T​(p.Pro32Leu) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000694 in 1,584,344 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 Pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. P32S) has been classified as Likely pathogenic.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000076 ( 0 hom. )

Consequence

GMPPB
NM_021971.4 missense

Scores

16
2
1

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:5

Conservation

PhyloP100: 7.30
Variant links:
Genes affected
GMPPB (HGNC:22932): (GDP-mannose pyrophosphorylase B) This gene is thought to encode a GDP-mannose pyrophosphorylase. The encoded protein catalyzes the conversion of mannose-1-phosphate and GTP to GDP-mannose, a reaction involved in the production of N-linked oligosaccharides. Alternatively spliced transcript variants encoding distinct isoforms have been described. [provided by RefSeq, Jan 2009]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 18 ACMG points.

PM1
In a strand (size 6) in uniprot entity GMPPB_HUMAN there are 7 pathogenic changes around while only 0 benign (100%) in NM_021971.4
PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr3-49723633-G-A is described in Lovd as [Likely_pathogenic].
PP3
MetaRNN computational evidence supports a deleterious effect, 0.984
PP5
Variant 3-49723632-G-A is Pathogenic according to our data. Variant chr3-49723632-G-A is described in ClinVar as [Pathogenic]. Clinvar id is 60544.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr3-49723632-G-A is described in Lovd as [Pathogenic]. Variant chr3-49723632-G-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
GMPPBNM_021971.4 linkc.95C>T p.Pro32Leu missense_variant Exon 1 of 9 ENST00000308388.7 NP_068806.2 Q9Y5P6-1
GMPPBNM_013334.4 linkc.95C>T p.Pro32Leu missense_variant Exon 1 of 8 NP_037466.3 Q9Y5P6-2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
GMPPBENST00000308388.7 linkc.95C>T p.Pro32Leu missense_variant Exon 1 of 9 1 NM_021971.4 ENSP00000311130.6 Q9Y5P6-1

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152266
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00
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:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000800
AC:
18
AN:
224944
Hom.:
0
AF XY:
0.0000990
AC XY:
12
AN XY:
121258
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000652
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:
0.0000873
Gnomad OTH exome
AF:
0.00131
GnomAD4 exome
AF:
0.0000761
AC:
109
AN:
1432078
Hom.:
0
Cov.:
32
AF XY:
0.0000732
AC XY:
52
AN XY:
710054
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.000170
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:
0.0000857
Gnomad4 OTH exome
AF:
0.000136
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152266
Hom.:
0
Cov.:
33
AF XY:
0.00
AC XY:
0
AN XY:
74394
show subpopulations
Gnomad4 AFR
AF:
0.00
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:
0.0000147
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000844
Hom.:
0
Bravo
AF:
0.0000416
ExAC
AF:
0.000115
AC:
14

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:5
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Pathogenic:2
Aug 03, 2022
Revvity Omics, Revvity
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Jan 12, 2024
GeneDx
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Published functional studies demonstrate dysfunctional GMPPB protein as the P32L variant caused the protein to form aggregates in the cytoplasm (PMID: 23768512); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Missense variants in this gene are a common cause of disease and they are underrepresented in the general population; Not observed at significant frequency in large population cohorts (gnomAD); This variant is associated with the following publications: (PMID: 23768512, 26310427, 24780531, 33060286, 34749429, 19901254, 25681410, 28554332, 28456886, 29437916, 30257713, 37681231, 35006422) -

Muscular dystrophy-dystroglycanopathy (congenital with intellectual disability), type B14 Pathogenic:1
Jul 11, 2013
OMIM
Significance: Pathogenic
Review Status: no assertion criteria provided
Collection Method: literature only

- -

Muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type A14;C3809221:Muscular dystrophy-dystroglycanopathy (congenital with intellectual disability), type B14;C4518000:Autosomal recessive limb-girdle muscular dystrophy type 2T Pathogenic:1
Jan 19, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This sequence change replaces proline, which is neutral and non-polar, with leucine, which is neutral and non-polar, at codon 32 of the GMPPB protein (p.Pro32Leu). This variant is present in population databases (rs397509426, gnomAD 0.02%). This missense change has been observed in individual(s) with GMPPB-related conditions (PMID: 23768512, 25681410, 28554332, 30257713). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. ClinVar contains an entry for this variant (Variation ID: 60544). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is expected to disrupt GMPPB protein function with a positive predictive value of 80%. Experimental studies have shown that this missense change affects GMPPB function (PMID: 23768512). For these reasons, this variant has been classified as Pathogenic. -

Autosomal recessive limb-girdle muscular dystrophy type 2T Pathogenic:1
Jan 13, 2015
HudsonAlpha Institute for Biotechnology, HudsonAlpha Institute for Biotechnology
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: research

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.91
BayesDel_addAF
Pathogenic
0.39
D
BayesDel_noAF
Pathogenic
0.58
CADD
Pathogenic
32
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.93
D;.;D
Eigen
Pathogenic
0.93
Eigen_PC
Pathogenic
0.78
FATHMM_MKL
Pathogenic
0.97
D
LIST_S2
Pathogenic
0.99
.;D;D
M_CAP
Pathogenic
0.95
D
MetaRNN
Pathogenic
0.98
D;D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Pathogenic
5.1
H;H;H
PrimateAI
Uncertain
0.76
T
PROVEAN
Pathogenic
-8.2
D;D;D
REVEL
Pathogenic
0.93
Sift
Pathogenic
0.0
D;D;D
Sift4G
Pathogenic
0.0010
D;D;D
Polyphen
1.0
D;D;D
Vest4
0.85
MutPred
0.88
Gain of ubiquitination at K31 (P = 0.0747);Gain of ubiquitination at K31 (P = 0.0747);Gain of ubiquitination at K31 (P = 0.0747);
MVP
0.94
MPC
1.5
ClinPred
0.99
D
GERP RS
4.0
Varity_R
0.98
gMVP
0.90

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: rs397509426; hg19: chr3-49761065; COSMIC: COSV105157022; COSMIC: COSV105157022; API