chr2-219500126-C-T

Variant names:

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2PP3_Strong

The NM_013335.4(GMPPA):c.46C>T(p.Arg16Cys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000335 in 1,604,584 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 12/21 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.00022 ( 0 hom., cov: 32)

Exomes 𝑓: 0.00035 ( 0 hom. )

Consequence

GMPPA
NM_013335.4 missense

Scores

Clinical Significance

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

Conservation

PhyloP100: 2.11

Variant links:

Genes affected

GMPPA (HGNC:22923): (GDP-mannose pyrophosphorylase A) This gene is thought to encode a GDP-mannose pyrophosphorylase. This enzyme catalyzes the reaction which converts mannose-1-phosphate and GTP to GDP-mannose which is involved in the production of N-linked oligosaccharides. [provided by RefSeq, Jul 2008]

GMPPA links:

ASIC4-AS1 (HGNC:40960): (ASIC4 antisense RNA 1)

ASIC4-AS1 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

PP3

MetaRNN computational evidence supports a deleterious effect, 0.949

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
GMPPA	NM_013335.4 link	c.46C>T	p.Arg16Cys	missense_variant	Exon 3 of 13	ENST00000313597.10	NP_037467.2	Q96IJ6-1A0A384MDS7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
GMPPA	ENST00000313597.10 link	c.46C>T	p.Arg16Cys	missense_variant	Exon 3 of 13	1	NM_013335.4	ENSP00000315925.6		Q96IJ6-1

Frequencies

GnomAD3 genomes

AF:

0.000217

AC:

AN:

152132

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.000169

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.0000655

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:

0.000367

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.000133

AC:

AN:

232656

Hom.:

AF XY:

0.000112

AC XY:

AN XY:

125448

show subpopulations

Gnomad AFR exome

AF:

0.000201

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:

0.0000494

Gnomad NFE exome

AF:

0.000261

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.000347

AC:

504

AN:

1452452

Hom.:

Cov.:

AF XY:

0.000338

AC XY:

244

AN XY:

721822

show subpopulations

Gnomad4 AFR exome

AF:

0.000120

Gnomad4 AMR exome

AF:

0.0000232

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.0000377

Gnomad4 NFE exome

AF:

0.000421

Gnomad4 OTH exome

AF:

0.000516

GnomAD4 genome

AF:

0.000217

AC:

AN:

152132

Hom.:

Cov.:

AF XY:

0.000202

AC XY:

AN XY:

74318

show subpopulations

Gnomad4 AFR

AF:

0.000169

Gnomad4 AMR

AF:

0.0000655

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.000367

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.000294

Hom.:

Bravo

AF:

0.000230

TwinsUK

AF:

0.000270

AC:

ALSPAC

AF:

0.000259

AC:

ExAC

AF:

0.000124

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Inborn genetic diseases

Uncertain:1

Jun 03, 2024

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.46C>T (p.R16C) alteration is located in exon 3 (coding exon 2) of the GMPPA gene. This alteration results from a C to T substitution at nucleotide position 46, causing the arginine (R) at amino acid position 16 to be replaced by a cysteine (C). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Alacrima, achalasia, and intellectual disability syndrome

Uncertain:1

Mar 05, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces arginine, which is basic and polar, with cysteine, which is neutral and slightly polar, at codon 16 of the GMPPA protein (p.Arg16Cys). This variant is present in population databases (rs201552488, gnomAD 0.02%). This variant has not been reported in the literature in individuals affected with GMPPA-related conditions. ClinVar contains an entry for this variant (Variation ID: 2379212). 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 GMPPA protein function with a positive predictive value of 80%. 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. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.90

BayesDel_addAF

Pathogenic

0.34

BayesDel_noAF

Pathogenic

0.55

CADD

Pathogenic

DANN

Pathogenic

1.0

DEOGEN2

Pathogenic

0.91

D;.;D;D;.;D;.

Eigen

Pathogenic

0.78

Eigen_PC

Uncertain

0.61

FATHMM_MKL

Uncertain

0.84

LIST_S2

Pathogenic

0.99

.;D;.;.;D;D;D

M_CAP

Pathogenic

0.63

MetaRNN

Pathogenic

0.95

D;D;D;D;D;D;D

MetaSVM

Pathogenic

1.0

MutationAssessor

Pathogenic

4.7

H;H;H;H;.;H;.

PrimateAI

Pathogenic

0.90

PROVEAN

Pathogenic

-7.5

D;D;D;D;D;D;.

REVEL

Pathogenic

0.92

Sift

Pathogenic

0.0

D;D;D;D;D;D;.

Sift4G

Pathogenic

0.0

D;D;D;D;D;D;D

Polyphen

1.0

D;D;D;D;.;D;.

Vest4

0.96

MVP

0.97

MPC

1.4

ClinPred

1.0

GERP RS

3.1

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Varity_R

0.98

gMVP

0.89

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.060

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