16-8801859-G-T

Variant summary

Our verdict is Likely pathogenic. The variant received 7 ACMG points: 7P and 0B. PM1PM2PM5PP2

The NM_000303.3(PMM2):​c.127G>T​(p.Val43Leu) variant causes a missense change. The variant allele was found at a frequency of 0.00000248 in 1,612,436 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Uncertain significance in ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. V43M) has been classified as Likely pathogenic.

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 33)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

PMM2
NM_000303.3 missense

Scores

2
10
6

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 3.65

Publications

1 publications found
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 Gene-Disease associations (from GenCC):
  • congenital disorder of glycosylation type I
    Inheritance: AR Classification: DEFINITIVE Submitted by: Myriad Women’s Health
  • PMM2-congenital disorder of glycosylation
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: PanelApp Australia, Labcorp Genetics (formerly Invitae), G2P, ClinGen, Orphanet
  • hyperinsulinemic hypoglycemia with polycystic kidney disease
    Inheritance: AR Classification: MODERATE Submitted by: ClinGen

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_pathogenic. The variant received 7 ACMG points.

PM1
In a hotspot region, there are 5 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 4 uncertain 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 chr16-8801859-G-A is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 495321.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
PP2
Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 89 curated pathogenic missense variants (we use a threshold of 10). The gene has 24 curated benign missense variants. Gene score misZ: -1.3872 (below the threshold of 3.09). Trascript score misZ: -1.8083 (below the threshold of 3.09). GenCC associations: The gene is linked to PMM2-congenital disorder of glycosylation, congenital disorder of glycosylation type I.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000303.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
PMM2
NM_000303.3
MANE Select
c.127G>Tp.Val43Leu
missense
Exon 2 of 8NP_000294.1A0A0S2Z4J6

Ensembl Transcripts

Sel.
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
PMM2
ENST00000268261.9
TSL:1 MANE Select
c.127G>Tp.Val43Leu
missense
Exon 2 of 8ENSP00000268261.4O15305-1
PMM2
ENST00000565221.5
TSL:1
n.127G>T
non_coding_transcript_exon
Exon 2 of 6ENSP00000457932.1H3BV34
PMM2
ENST00000566540.5
TSL:1
n.127G>T
non_coding_transcript_exon
Exon 2 of 6ENSP00000454284.1H3BM92

Frequencies

GnomAD3 genomes
AF:
0.0000197
AC:
3
AN:
152212
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000241
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000654
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
GnomAD4 exome
AF:
6.85e-7
AC:
1
AN:
1460224
Hom.:
0
Cov.:
30
AF XY:
0.00
AC XY:
0
AN XY:
726362
show subpopulations
⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.00
AC:
0
AN:
33398
American (AMR)
AF:
0.00
AC:
0
AN:
44710
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26120
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39620
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86180
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53302
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5764
European-Non Finnish (NFE)
AF:
9.00e-7
AC:
1
AN:
1110838
Other (OTH)
AF:
0.00
AC:
0
AN:
60292
⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.275
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000197
AC:
3
AN:
152212
Hom.:
0
Cov.:
33
AF XY:
0.0000269
AC XY:
2
AN XY:
74366
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41452
American (AMR)
AF:
0.0000654
AC:
1
AN:
15280
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5200
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4834
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10618
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68036
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.425
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.0000113

ClinVar

ClinVar submissions as Germline
Significance:Uncertain significance
Revision:criteria provided, multiple submitters, no conflicts
View on ClinVar
Pathogenic
VUS
Benign
Condition
-
2
-
PMM2-congenital disorder of glycosylation (2)
-
1
-
not specified (1)

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.46
BayesDel_addAF
Pathogenic
0.40
D
BayesDel_noAF
Pathogenic
0.34
CADD
Benign
21
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.53
D
Eigen
Benign
0.015
Eigen_PC
Benign
0.21
FATHMM_MKL
Uncertain
0.95
D
LIST_S2
Uncertain
0.95
D
M_CAP
Uncertain
0.16
D
MetaRNN
Uncertain
0.44
T
MetaSVM
Uncertain
0.71
D
MutationAssessor
Benign
1.4
L
PhyloP100
3.7
PrimateAI
Uncertain
0.55
T
PROVEAN
Benign
-0.34
N
REVEL
Uncertain
0.55
Sift
Benign
0.34
T
Sift4G
Benign
0.39
T
Polyphen
0.50
P
Vest4
0.38
MVP
0.90
MPC
0.0091
ClinPred
0.38
T
GERP RS
6.0
Varity_R
0.41
gMVP
0.82
Mutation Taster
=38/62
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.050
Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

Other links and lift over

dbSNP: rs376754460; hg19: chr16-8895716; API