chr16-8847753-C-G

Variant names:

• chr16-8847753-C-G
• rs104894531
• NM_000303.3:c.669C>G

Variant summary

Our verdict is Pathogenic. The variant received 21 ACMG points: 21P and 0B. PS1_Very_Strong PM1 PM2 PM5 PP2 PP3_Strong PP5_Moderate

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 (★). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Likely pathogenic in ClinVar. 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 criteria provided, single submitter P:2
• Conservation: PhyloP100: 1.04
• Publications: 6 publications found

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: G2P, Labcorp Genetics (formerly Invitae), Orphanet, PanelApp Australia, ClinGen

ENSG00000260350 (HGNC:58482):

ACMG classification

Our verdict: Pathogenic. The variant received 21 ACMG points.

• PS1: Transcript NM_000303.3 (PMM2) is affected with MISSENSE_VARIANT having same AA change as one Pathogenic present in ClinVar.
• PM1: In a hotspot region, there are 14 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 10 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 chr16-8847751-G-A is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 2429140.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.
• 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 VariationId is 7714.Status of the report is criteria_provided_single_submitter, 1 stars.

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.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	PMM2	NM_000303.3	MANE Select	c.669C>G	p.Asp223Glu	missense	Exon 8 of 8	NP_000294.1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	PMM2	ENST00000268261.9	TSL:1 MANE Select	c.669C>G	p.Asp223Glu	missense	Exon 8 of 8	ENSP00000268261.4
	PMM2	ENST00000565221.5	TSL:1	n.*287C>G		non_coding_transcript_exon	Exon 6 of 6	ENSP00000457932.1
	PMM2	ENST00000566540.5	TSL:1	n.*291C>G		non_coding_transcript_exon	Exon 6 of 6	ENSP00000454284.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 33

ClinVar

ClinVar submissions as Germline

Significance: Pathogenic

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
2	-	-	PMM2-congenital disorder of glycosylation (2)

Computational scores

Source: dbNSFP v4.9

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
Eigen	Uncertain	0.22
Eigen_PC	Benign	0.20
FATHMM_MKL	Uncertain	0.91	D
LIST_S2	Pathogenic	0.99	D
M_CAP	Pathogenic	0.41	D
MetaRNN	Pathogenic	0.98	D
MetaSVM	Pathogenic	1.2	D
MutationAssessor	Pathogenic	3.9	H
PhyloP100		1.0
PrimateAI	Uncertain	0.61	T
PROVEAN	Uncertain	-3.0	D
REVEL	Pathogenic	0.80
Sift	Uncertain	0.0030	D
Sift4G	Uncertain	0.0060	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
Mutation Taster		=1/99	disease causing (ClinVar)

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

Other links and lift over

dbSNP: rs104894531; hg19: chr16-8941610;