rs763971677

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PVS1PM2PP5_Moderate

The NM_021971.4(GMPPB):​c.790C>T​(p.Gln264Ter) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000206 in 1,459,646 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 (★).

Frequency

Genomes: not found (cov: 33)
Exomes 𝑓: 0.0000021 ( 0 hom. )

Consequence

GMPPB
NM_021971.4 stop_gained

Scores

3
3
1

Clinical Significance

Pathogenic criteria provided, single submitter P:1

Conservation

PhyloP100: 0.780
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 12 ACMG points.

PVS1
Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most 50 bp of the penultimate exon, not predicted to undergo nonsense mediated mRNA decay. There are 24 pathogenic variants in the truncated region.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 3-49722126-G-A is Pathogenic according to our data. Variant chr3-49722126-G-A is described in ClinVar as [Pathogenic]. Clinvar id is 571713.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr3-49722126-G-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
GMPPBNM_021971.4 linkuse as main transcriptc.790C>T p.Gln264Ter stop_gained 8/9 ENST00000308388.7 NP_068806.2
GMPPBNM_013334.4 linkuse as main transcriptc.790C>T p.Gln264Ter stop_gained 8/8 NP_037466.3

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
GMPPBENST00000308388.7 linkuse as main transcriptc.790C>T p.Gln264Ter stop_gained 8/91 NM_021971.4 ENSP00000311130 P1Q9Y5P6-1

Frequencies

GnomAD3 genomes
Cov.:
33
GnomAD3 exomes
AF:
0.00000402
AC:
1
AN:
248796
Hom.:
0
AF XY:
0.00
AC XY:
0
AN XY:
134614
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 SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000896
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000206
AC:
3
AN:
1459646
Hom.:
0
Cov.:
44
AF XY:
0.00000413
AC XY:
3
AN XY:
725848
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
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:
0.00000180
Gnomad4 OTH exome
AF:
0.0000166
GnomAD4 genome
Cov.:
33
Bravo
AF:
0.00000378
ExAC
AF:
0.00000824
AC:
1

ClinVar

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

Submissions by phenotype

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
Pathogenic, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpJan 24, 2024This sequence change creates a premature translational stop signal (p.Gln264*) in the GMPPB gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in GMPPB are known to be pathogenic (PMID: 23768512, 26310427). This variant is present in population databases (rs763971677, gnomAD 0.0009%). This premature translational stop signal has been observed in individual(s) with GMPPB-related conditions (PMID: 25770200). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 571713). For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.62
D
BayesDel_noAF
Pathogenic
0.52
CADD
Pathogenic
36
DANN
Uncertain
0.99
Eigen
Pathogenic
0.72
Eigen_PC
Uncertain
0.54
FATHMM_MKL
Uncertain
0.92
D
MutationTaster
Benign
1.0
A;A;D;D
Vest4
0.37
GERP RS
4.1

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: rs763971677; hg19: chr3-49759559; API