Genetic Variant PMM1:p.Val191Ile (chr22-41577903-C-T) – ACMG Classification: Uncertain_significance (2 pts)

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_002676.3(PMM1):c.571G>A(p.Val191Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000155 in 1,613,132 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000016 ( 0 hom. )

Consequence

PMM1
NM_002676.3 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 1.43

Variant links:

Genes affected

PMM1 (HGNC:9114): (phosphomannomutase 1) Phosphomannomutase catalyzes the conversion between D-mannose 6-phosphate and D-mannose 1-phosphate which is a substrate for GDP-mannose synthesis. GDP-mannose is used for synthesis of dolichol-phosphate-mannose, which is essential for N-linked glycosylation and thus the secretion of several glycoproteins as well as for the synthesis of glycosyl-phosphatidyl-inositol (GPI) anchored proteins. [provided by RefSeq, Jul 2008]

PMM1 links:

CSDC2 (HGNC:30359): (cold shock domain containing C2) Predicted to enable mRNA 3'-UTR binding activity. Predicted to be involved in regulation of mRNA stability. Predicted to be located in nucleus. Predicted to be active in cytoplasm. [provided by Alliance of Genome Resources, Apr 2022]

CSDC2 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 2 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
PMM1	NM_002676.3 link	c.571G>A	p.Val191Ile	missense_variant	Exon 7 of 8	ENST00000216259.8	NP_002667.2	Q92871A0A024R1U5

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
PMM1	ENST00000216259.8 link	c.571G>A	p.Val191Ile	missense_variant	Exon 7 of 8	1	NM_002676.3	ENSP00000216259.7		Q92871

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152206

Hom.:

Cov.:

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:

0.00000797

AC:

AN:

250846

Hom.:

AF XY:

0.00

AC XY:

AN XY:

135800

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:

0.0000177

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000164

AC:

AN:

1460926

Hom.:

Cov.:

AF XY:

0.0000138

AC XY:

AN XY:

726780

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:

0.0000232

Gnomad4 FIN exome

AF:

0.0000380

Gnomad4 NFE exome

AF:

0.0000171

Gnomad4 OTH exome

AF:

0.0000166

GnomAD4 genome

AF:

0.00000657

AC:

AN:

152206

Hom.:

Cov.:

AF XY:

0.0000135

AC XY:

AN XY:

74348

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:

0.0000282

Hom.:

Bravo

AF:

0.00000756

ExAC

AF:

0.00000824

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

not specified

Uncertain:1

Mar 08, 2025

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.571G>A (p.V191I) alteration is located in exon 7 (coding exon 7) of the PMM1 gene. This alteration results from a G to A substitution at nucleotide position 571, causing the valine (V) at amino acid position 191 to be replaced by an isoleucine (I). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.11

BayesDel_addAF

Uncertain

0.060

BayesDel_noAF

Benign

-0.14

CADD

Benign

DANN

Uncertain

0.99

DEOGEN2

Uncertain

0.74

Eigen

Benign

-0.35

Eigen_PC

Benign

-0.29

FATHMM_MKL

Benign

0.75

LIST_S2

Uncertain

0.92

M_CAP

Pathogenic

0.38

MetaRNN

Uncertain

0.57

MetaSVM

Pathogenic

0.92

MutationAssessor

Benign

0.70

PrimateAI

Uncertain

0.55

PROVEAN

Benign

-0.72

REVEL

Uncertain

0.46

Sift

Benign

0.091

Sift4G

Benign

0.17

Polyphen

0.0030

Vest4

0.056

MutPred

0.79

Gain of catalytic residue at P193 (P = 0.0631);

MVP

0.85

MPC

0.36

ClinPred

0.16

GERP RS

4.2

Varity_R

0.084

gMVP

0.40

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.010

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