rs1187245939

Variant summary

Our verdict is Likely pathogenic. Variant got 9 ACMG points: 9P and 0B. PM1PM2PP3_StrongPP5

The NM_000303.3(PMM2):​c.305A>G​(p.Tyr102Cys) variant causes a missense change. The variant allele was found at a frequency of 0.00000248 in 1,613,414 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 Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: š‘“ 0.0000066 ( 0 hom., cov: 33)
Exomes š‘“: 0.0000021 ( 0 hom. )

Consequence

PMM2
NM_000303.3 missense

Scores

11
7
1

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1U:2

Conservation

PhyloP100: 6.91
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 Likely_pathogenic. Variant got 9 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, 0.939
PP5
Variant 16-8806365-A-G is Pathogenic according to our data. Variant chr16-8806365-A-G is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 550875.We mark this variant Likely_pathogenic, oryginal submissions are: {Likely_pathogenic=1, Uncertain_significance=2}.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
PMM2NM_000303.3 linkc.305A>G p.Tyr102Cys missense_variant Exon 4 of 8 ENST00000268261.9 NP_000294.1 O15305-1A0A0S2Z4J6Q59F02
PMM2XM_047434215.1 linkc.56A>G p.Tyr19Cys missense_variant Exon 2 of 6 XP_047290171.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
PMM2ENST00000268261.9 linkc.305A>G p.Tyr102Cys missense_variant Exon 4 of 8 1 NM_000303.3 ENSP00000268261.4 O15305-1

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152220
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000241
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
GnomAD4 exome
AF:
0.00000205
AC:
3
AN:
1461194
Hom.:
0
Cov.:
29
AF XY:
0.00000275
AC XY:
2
AN XY:
726978
show subpopulations
Gnomad4 AFR exome
AF:
0.0000299
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.0000252
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
9.00e-7
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152220
Hom.:
0
Cov.:
33
AF XY:
0.0000134
AC XY:
1
AN XY:
74366
show subpopulations
Gnomad4 AFR
AF:
0.0000241
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
Bravo
AF:
0.00000378

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:1Uncertain:2
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Pathogenic:1
Aug 13, 2024
GeneDx
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Published functional studies demonstrate a damaging effect, as the Y102C variant results in reduced enzymatic activity in vitro (PMID: 35789514); De novo variant with confirmed parentage in a patient referred for genetic testing at GeneDx; however, the reported clinical features are only partially consistent with the features typically observed in individuals with pathogenic variants in this gene; Not observed at 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: 23430838, 35789514, 34732400) -

not specified Uncertain:1
Jul 30, 2024
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Variant summary: PMM2 c.305A>G (p.Tyr102Cys) results in a non-conservative amino acid change in the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant was absent in 251452 control chromosomes. c.305A>G has been reported in the literature in an compound heterozygous individual affected with clinical features of Congenital Disorder Of Glycosylation Type 1a (Schon_2021). These data do not allow any conclusion about variant significance. At least one publication reports experimental evidence evaluating an impact on protein function. The most pronounced variant effect results in 30%-50% of normal activity in an in vitro assay (Segovia-Falquina_2022). The following publications have been ascertained in the context of this evaluation (PMID: 34732400, 35789514). ClinVar contains an entry for this variant (Variation ID: 550875). Based on the evidence outlined above, the variant was classified as VUS-possibly pathogenic. -

PMM2-congenital disorder of glycosylation Uncertain:1
Mar 22, 2017
Counsyl
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.36
BayesDel_addAF
Pathogenic
0.54
D
BayesDel_noAF
Pathogenic
0.54
CADD
Pathogenic
26
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.87
D;D
Eigen
Pathogenic
0.74
Eigen_PC
Pathogenic
0.73
FATHMM_MKL
Uncertain
0.95
D
LIST_S2
Uncertain
0.86
D;D
M_CAP
Pathogenic
0.41
D
MetaRNN
Pathogenic
0.94
D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Uncertain
2.6
.;M
PrimateAI
Uncertain
0.75
T
PROVEAN
Pathogenic
-5.2
D;D
REVEL
Pathogenic
0.94
Sift
Pathogenic
0.0
D;D
Sift4G
Uncertain
0.0020
D;D
Polyphen
1.0
.;D
Vest4
0.93
MutPred
0.74
.;Loss of catalytic residue at Y102 (P = 0.0592);
MVP
0.96
MPC
0.0093
ClinPred
0.99
D
GERP RS
5.6
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.89
gMVP
0.96

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: rs1187245939; hg19: chr16-8900222; API