rs768327938

Positions:

chr3-49721879-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PM2PM5PP3

The NM_021971.4(GMPPB):c.956G>A(p.Arg319His) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000018 in 1,613,846 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 Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R319S) has been classified as Pathogenic.

Frequency

Genomes: 𝑓 0.000092 ( 0 hom., cov: 33)

Exomes 𝑓: 0.000010 ( 0 hom. )

Consequence

GMPPB
NM_021971.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 7.81

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]

GMPPB links:

GMPPB (HGNC:):

GMPPB links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 5 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

PM5

Other missense variant is known to change same aminoacid residue: Variant chr3-49721880-G-T is described in Lovd as [Pathogenic].

PP3

MetaRNN computational evidence supports a deleterious effect, 0.755

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
GMPPB	NM_021971.4 linkuse as main transcript	c.956G>A	p.Arg319His	missense_variant	9/9	ENST00000308388.7	NP_068806.2	Q9Y5P6-1
GMPPB	NM_013334.4 linkuse as main transcript	c.1037G>A	p.Arg346His	missense_variant	8/8		NP_037466.3	Q9Y5P6-2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
GMPPB	ENST00000308388.7 linkuse as main transcript	c.956G>A	p.Arg319His	missense_variant	9/9	1	NM_021971.4	ENSP00000311130.6		Q9Y5P6-1

Frequencies

GnomAD3 genomes

AF:

0.0000920

AC:

AN:

152208

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.000338

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

GnomAD3 exomes

AF:

0.0000239

AC:

AN:

251312

Hom.:

AF XY:

0.0000147

AC XY:

AN XY:

135860

show subpopulations

Gnomad AFR exome

AF:

0.000246

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:

0.0000176

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000103

AC:

AN:

1461638

Hom.:

Cov.:

AF XY:

0.0000110

AC XY:

AN XY:

727142

show subpopulations

Gnomad4 AFR exome

AF:

0.000149

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000252

Gnomad4 SAS exome

AF:

0.0000232

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00000540

Gnomad4 OTH exome

AF:

0.0000166

GnomAD4 genome

AF:

0.0000920

AC:

AN:

152208

Hom.:

Cov.:

AF XY:

0.000108

AC XY:

AN XY:

74356

show subpopulations

Gnomad4 AFR

AF:

0.000338

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:

0.00

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000386

Hom.:

Bravo

AF:

0.0000907

ExAC

AF:

0.0000247

AC:

EpiCase

AF:

0.00

EpiControl

AF:

0.0000593

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

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

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jun 27, 2022

This sequence change replaces arginine, which is basic and polar, with histidine, which is basic and polar, at codon 319 of the GMPPB protein (p.Arg319His). This variant is present in population databases (rs768327938, gnomAD 0.03%). This variant has not been reported in the literature in individuals affected with GMPPB-related conditions. ClinVar contains an entry for this variant (Variation ID: 541079). Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). This variant disrupts the p.Arg319 amino acid residue in GMPPB. Other variant(s) that disrupt this residue have been observed in individuals with GMPPB-related conditions (PMID: 25681410, 33756069), which suggests that this may be a clinically significant amino acid residue. 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. -

not provided

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Revvity Omics, Revvity

Jun 21, 2019

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.74

BayesDel_addAF

Uncertain

0.021

BayesDel_noAF

Uncertain

0.090

CADD

Uncertain

DANN

Pathogenic

1.0

DEOGEN2

Uncertain

0.61

D;.;D

Eigen

Uncertain

0.64

Eigen_PC

Uncertain

0.66

FATHMM_MKL

Pathogenic

0.98

LIST_S2

Benign

0.68

.;T;D

M_CAP

Uncertain

0.24

MetaRNN

Pathogenic

0.76

D;D;D

MetaSVM

Uncertain

0.12

MutationAssessor

Pathogenic

3.5

M;.;M

PrimateAI

Uncertain

0.58

PROVEAN

Pathogenic

-4.9

D;D;D

REVEL

Pathogenic

0.65

Sift

Benign

0.034

D;D;D

Sift4G

Benign

0.10

T;D;T

Polyphen

0.75

P;P;P

Vest4

0.84

MutPred

0.63

Loss of MoRF binding (P = 0.0139);.;Loss of MoRF binding (P = 0.0139);

MVP

0.91

MPC

1.7

ClinPred

0.92

GERP RS

5.4

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.9

Varity_R

0.40

gMVP

0.80

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

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over