rs751986971

Positions:

chr16-8804788-T-G

Variant summary

Our verdict is Likely pathogenic. Variant got 7 ACMG points: 7P and 0B. PM1PM2PM5PP3

The NM_000303.3(PMM2):c.200T>G(p.Val67Gly) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000075 in 1,613,116 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). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. V67M) has been classified as Likely pathogenic.

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000080 ( 0 hom. )

Consequence

PMM2
NM_000303.3 missense

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:2U:3

Conservation

PhyloP100: 7.49

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]

PMM2 links:

PMM2 (HGNC:):

PMM2 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 7 ACMG points.

PM1

In a strand (size 4) in uniprot entity PMM2_HUMAN there are 6 pathogenic changes around while only 0 benign (100%) in NM_000303.3

PM2

Very rare variant in population databases, with high coverage;

PM5

Other missense variant is known to change same aminoacid residue: Variant chrnull-null-null-null is described in UniProt as null.

PP3

MetaRNN computational evidence supports a deleterious effect, 0.812

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
PMM2	NM_000303.3 linkuse as main transcript	c.200T>G	p.Val67Gly	missense_variant	3/8	ENST00000268261.9	NP_000294.1	O15305-1A0A0S2Z4J6Q59F02
PMM2	XM_047434215.1 linkuse as main transcript	c.7-1528T>G		intron_variant			XP_047290171.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
PMM2	ENST00000268261.9 linkuse as main transcript	c.200T>G	p.Val67Gly	missense_variant	3/8	1	NM_000303.3	ENSP00000268261.4		O15305-1

Frequencies

GnomAD3 genomes

AF:

0.0000263

AC:

AN:

152218

Hom.:

Cov.:

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:

0.0000441

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000199

AC:

AN:

251388

Hom.:

AF XY:

0.0000368

AC XY:

AN XY:

135888

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:

0.0000440

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000801

AC:

117

AN:

1460898

Hom.:

Cov.:

AF XY:

0.0000839

AC XY:

AN XY:

726814

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:

0.000103

Gnomad4 OTH exome

AF:

0.0000331

GnomAD4 genome

AF:

0.0000263

AC:

AN:

152218

Hom.:

Cov.:

AF XY:

0.0000134

AC XY:

AN XY:

74374

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:

0.0000441

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000502

Hom.:

Bravo

AF:

0.0000227

ExAC

AF:

0.0000165

AC:

EpiCase

AF:

0.000164

EpiControl

AF:

0.00

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:2Uncertain:3

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

PMM2-congenital disorder of glycosylation

Pathogenic:2Uncertain:1

Uncertain significance, criteria provided, single submitter	clinical testing	Counsyl	Nov 08, 2017	- -
Pathogenic, criteria provided, single submitter	clinical testing	Fulgent Genetics, Fulgent Genetics	Apr 10, 2024	- -
Pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jan 08, 2024	This sequence change replaces valine, which is neutral and non-polar, with glycine, which is neutral and non-polar, at codon 67 of the PMM2 protein (p.Val67Gly). This variant is present in population databases (rs751986971, gnomAD 0.004%). This missense change has been observed in individual(s) with congenital disorder of gylcosylation type Ia (PMID: 16435227). 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: 285370). 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 PMM2 protein function with a positive predictive value of 95%. This variant disrupts the p.Val67 amino acid residue in PMM2. Other variant(s) that disrupt this residue have been observed in individuals with PMM2-related conditions (PMID: 11058896), which suggests that this may be a clinically significant amino acid residue. For these reasons, this variant has been classified as Pathogenic. -

not specified

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Feb 20, 2023

Variant summary: PMM2 c.200T>G (p.Val67Gly) results in a non-conservative amino acid change in the encoded protein sequence. Four of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 2e-05 in 251388 control chromosomes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.200T>G has been reported in the literature in at least one individual affected with Congenital Disorder Of Glycosylation Type 1a. These data do not allow any conclusion about variant significance. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Three clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation (Pathogenic n=1, VUS n=2). In addition, p.V67M has also been reported to associate with Congenital Disorder Of Glycosylation Type 1a. Based on the evidence outlined above, the variant was classified as VUS-possibly pathogenic. -

not provided

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Eurofins Ntd Llc (ga)

Dec 14, 2015

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.72

BayesDel_addAF

Pathogenic

0.43

BayesDel_noAF

Pathogenic

0.51

CADD

Pathogenic

DANN

Uncertain

1.0

DEOGEN2

Pathogenic

0.80

D;D

Eigen

Pathogenic

0.78

Eigen_PC

Pathogenic

0.78

FATHMM_MKL

Pathogenic

0.97

LIST_S2

Uncertain

0.94

D;D

M_CAP

Uncertain

0.12

MetaRNN

Pathogenic

0.81

D;D

MetaSVM

Pathogenic

1.1

MutationAssessor

Uncertain

2.3

.;M

PrimateAI

Uncertain

0.58

PROVEAN

Pathogenic

-5.3

D;D

REVEL

Pathogenic

0.92

Sift

Benign

0.15

T;T

Sift4G

Benign

0.15

T;T

Polyphen

1.0

.;D

Vest4

0.69

MVP

0.99

MPC

0.041

ClinPred

0.87

GERP RS

5.9

Varity_R

0.89

gMVP

0.97

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.

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