chr16-8806383-C-T

Variant summary

Our verdict is Pathogenic. Variant got 16 ACMG points: 16P and 0B. PM1PM2PP3_StrongPP5_Very_Strong

The NM_000303.3(PMM2):​c.323C>T​(p.Ala108Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000484 in 1,612,342 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 Likely pathogenic (★★). Synonymous variant affecting the same amino acid position (i.e. A108A) has been classified as Benign.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000053 ( 0 hom. )

Consequence

PMM2
NM_000303.3 missense

Scores

8
7
4

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:8

Conservation

PhyloP100: 2.60
Variant links:
Genes affected
PMM2 (HGNC:9115): (phosphomannomutase 2) The protein encoded by this gene catalyzes the isomerization of mannose 6-phosphate to mannose 1-phosphate, which is a precursor to GDP-mannose necessary for the synthesis of dolichol-P-oligosaccharides. Mutations in this gene have been shown to cause defects in glycoprotein biosynthesis, which manifests as carbohydrate-deficient glycoprotein syndrome type I. [provided by RefSeq, Jul 2008]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 16 ACMG points.

PM1
In a helix (size 16) in uniprot entity PMM2_HUMAN there are 7 pathogenic changes around while only 0 benign (100%) in NM_000303.3
PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.984
PP5
Variant 16-8806383-C-T is Pathogenic according to our data. Variant chr16-8806383-C-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 92800.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr16-8806383-C-T is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
PMM2NM_000303.3 linkuse as main transcriptc.323C>T p.Ala108Val missense_variant 4/8 ENST00000268261.9 NP_000294.1
PMM2XM_047434215.1 linkuse as main transcriptc.74C>T p.Ala25Val missense_variant 2/6 XP_047290171.1

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
PMM2ENST00000268261.9 linkuse as main transcriptc.323C>T p.Ala108Val missense_variant 4/81 NM_000303.3 ENSP00000268261 P1O15305-1

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152108
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:
0.0000119
AC:
3
AN:
251440
Hom.:
0
AF XY:
0.0000147
AC XY:
2
AN XY:
135886
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:
0.0000264
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000527
AC:
77
AN:
1460234
Hom.:
0
Cov.:
29
AF XY:
0.0000344
AC XY:
25
AN XY:
726610
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:
0.0000639
Gnomad4 OTH exome
AF:
0.0000995
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152108
Hom.:
0
Cov.:
33
AF XY:
0.00
AC XY:
0
AN XY:
74298
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:
0.0000574
Hom.:
0
Bravo
AF:
0.0000264
TwinsUK
AF:
0.000270
AC:
1
ALSPAC
AF:
0.00
AC:
0
ExAC
AF:
0.0000165
AC:
2
EpiCase
AF:
0.000164
EpiControl
AF:
0.000119

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:8
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

PMM2-congenital disorder of glycosylation Pathogenic:5
Likely pathogenic, criteria provided, single submitterclinical testingFulgent Genetics, Fulgent GeneticsAug 12, 2021- -
Pathogenic, criteria provided, single submitterclinical testingBaylor GeneticsMar 12, 2024- -
Pathogenic, criteria provided, single submitterresearchMolecular Medicine for Neurodegenerative and Neuromuscular Diseases Unit, IRCCS Fondazione Stella MarisJan 04, 2021- -
Likely pathogenic, criteria provided, single submitterclinical testingMyriad Genetics, Inc.Nov 10, 2021NM_000303.2(PMM2):c.323C>T(A108V) is a missense variant classified as likely pathogenic in the context of congenital disorder of glycosylation type Ia. A108V has been observed in cases with relevant disease (PMID: 32635232, Gurtunca_2013 _(no PMID; abstract), 25355454, 25497157, 15844218). Functional assessments of this variant are not available in the literature. A108V has been observed in population frequency databases (gnomAD: NFE 0.002%). In summary, NM_000303.2(PMM2):c.323C>T(A108V) is a missense variant that has been observed more frequently in cases with the relevant disease than in healthy populations. Please note: this variant was assessed in the context of healthy population screening. -
Pathogenic, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpJan 24, 2024This sequence change replaces alanine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 108 of the PMM2 protein (p.Ala108Val). This variant is present in population databases (rs200503569, gnomAD 0.003%). This missense change has been observed in individual(s) with PMM2-related conditions (PMID: 9140401, 15844218, 25355454). 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: 92800). 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) has been performed at Invitae for this missense variant, however the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on PMM2 protein function. For these reasons, this variant has been classified as Pathogenic. -
not provided Pathogenic:2
Pathogenic, criteria provided, single submitterclinical testingGeneDxJul 01, 2022Not observed at a significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 11058895, 9781052, 15771971, 9497260, 9425221, 9140401, 25497157, 25355454, 15844218, 34234304, 34480478) -
Likely pathogenic, criteria provided, single submitterclinical testingEurofins Ntd Llc (ga)Aug 30, 2013- -
Premature ovarian failure Pathogenic:1
Pathogenic, criteria provided, single submitterresearchMedical Cytogenetics and Molecular Genetics Laboratory, IRCCS Istituto Auxologico ItalianoMar 02, 2020- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.74
BayesDel_addAF
Pathogenic
0.43
D
BayesDel_noAF
Pathogenic
0.44
CADD
Uncertain
25
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.91
D;D
Eigen
Benign
0.14
Eigen_PC
Benign
0.18
FATHMM_MKL
Uncertain
0.93
D
LIST_S2
Uncertain
0.91
D;D
M_CAP
Uncertain
0.22
D
MetaRNN
Pathogenic
0.98
D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Pathogenic
3.3
.;M
MutationTaster
Benign
1.0
D;D;D;D;D
PrimateAI
Uncertain
0.64
T
PROVEAN
Uncertain
-3.5
D;D
REVEL
Pathogenic
0.72
Sift
Uncertain
0.018
D;D
Sift4G
Benign
0.10
T;T
Polyphen
0.61
.;P
Vest4
0.84
MutPred
0.97
.;Gain of methylation at K109 (P = 0.0485);
MVP
0.92
MPC
0.016
ClinPred
0.90
D
GERP RS
5.6
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.77
gMVP
0.85

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.

Other links and lift over

dbSNP: rs200503569; hg19: chr16-8900240; COSMIC: COSV51631655; COSMIC: COSV51631655; API