16-8847753-C-G

Position:

• chr16-8847753-C-G

Variant summary

Our verdict is Pathogenic. Variant got 11 ACMG points: 11P and 0B. PM1 PM2 PM5 PP3_Strong PP5

The NM_000303.3(PMM2):​c.669C>G​(p.Asp223Glu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. D223N) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 33)
• Consequence: PMM2 NM_000303.3 missense
• Clinical Significance: Pathogenic no assertion criteria provided P:1
• Conservation: PhyloP100: 1.04

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]

(HGNC:):

ACMG classification

Verdict is Pathogenic. Variant got 11 ACMG points.

• PM1: In a chain Phosphomannomutase 2 (size 244) in uniprot entity PMM2_HUMAN there are 79 pathogenic changes around while only 2 benign (98%) 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, 0.981
• PP5: Variant 16-8847753-C-G is Pathogenic according to our data. Variant chr16-8847753-C-G is described in ClinVar as [Pathogenic]. Clinvar id is 7714.Status of the report is no_assertion_criteria_provided, 0 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
PMM2	NM_000303.3	c.669C>G	p.Asp223Glu	missense_variant	8/8	ENST00000268261.9	NP_000294.1
PMM2	XM_047434215.1	c.420C>G	p.Asp140Glu	missense_variant	6/6		XP_047290171.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
PMM2	ENST00000268261.9	c.669C>G	p.Asp223Glu	missense_variant	8/8	1	NM_000303.3	ENSP00000268261	P1
	ENST00000567942.1	n.327G>C		non_coding_transcript_exon_variant	2/2	3

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 33

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: no assertion criteria provided

Submissions by phenotype

PMM2-congenital disorder of glycosylation Pathogenic:1

Pathogenic, no assertion criteria provided

literature only

OMIM

Jul 01, 1998

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.86
BayesDel_addAF	Pathogenic	0.51	D
BayesDel_noAF	Pathogenic	0.50
CADD	Benign	22
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.92	D;D;.
Eigen	Uncertain	0.22
Eigen_PC	Benign	0.20
FATHMM_MKL	Uncertain	0.91	D
LIST_S2	Pathogenic	0.99	D;D;D
M_CAP	Pathogenic	0.41	D
MetaRNN	Pathogenic	0.98	D;D;D
MetaSVM	Pathogenic	1.2	D
MutationAssessor	Pathogenic	3.9	.;H;.
MutationTaster	Benign	1.0	A;A;A;A;A
PrimateAI	Uncertain	0.61	T
PROVEAN	Uncertain	-3.0	D;D;D
REVEL	Pathogenic	0.80
Sift	Uncertain	0.0030	D;D;D
Sift4G	Uncertain	0.0060	D;D;D
Polyphen		0.75	.;P;.
Vest4		0.98
MutPred		0.95		.;Gain of disorder (P = 0.1362);.;
MVP		0.92
MPC		0.017
ClinPred		0.99	D
GERP RS		2.9
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.94
gMVP		0.86

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

Other links and lift over

dbSNP: rs104894531; hg19: chr16-8941610;