chr6-131860388-G-C

Variant names:

• chr6-131860388-G-C
• rs121908248
• NM_006208.3:c.797G>C

Variant summary

Our verdict is Uncertain significance. The variant received 5 ACMG points: 5P and 0B. PM2 PM5 PP3

The NM_006208.3(ENPP1):​c.797G>C​(p.Gly266Ala) variant causes a missense, splice region change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000659 in 151,846 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 15/24 in silico tools predict a damaging outcome for this variant. 2/3 splice prediction tools predicting alterations to normal splicing. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G266R) has been classified as Likely pathogenic.

• Frequency: Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
• Consequence: ENPP1 NM_006208.3 missense, splice_region
• Scores: Splicing: ADA: 0.9727
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 9.27
• Publications: 6 publications found

Genes affected

ENPP1 (HGNC:3356): (ectonucleotide pyrophosphatase/phosphodiesterase 1) This gene is a member of the ecto-nucleotide pyrophosphatase/phosphodiesterase (ENPP) family. The encoded protein is a type II transmembrane glycoprotein comprising two identical disulfide-bonded subunits. This protein has broad specificity and cleaves a variety of substrates, including phosphodiester bonds of nucleotides and nucleotide sugars and pyrophosphate bonds of nucleotides and nucleotide sugars. This protein may function to hydrolyze nucleoside 5' triphosphates to their corresponding monophosphates and may also hydrolyze diadenosine polyphosphates. Mutations in this gene have been associated with 'idiopathic' infantile arterial calcification, ossification of the posterior longitudinal ligament of the spine (OPLL), and insulin resistance. [provided by RefSeq, Jul 2008]

ENPP1 Gene-Disease associations (from GenCC):

• arterial calcification, generalized, of infancy, 1

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P, ClinGen
• hypopigmentation-punctate palmoplantar keratoderma syndrome

  Inheritance: AD Classification: STRONG, SUPPORTIVE, LIMITED Submitted by: ClinGen, G2P, Orphanet, Ambry Genetics, Labcorp Genetics (formerly Invitae), Genomics England PanelApp
• hypophosphatemic rickets, autosomal recessive, 2

  Inheritance: AR Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
• arterial calcification of infancy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• autosomal recessive hypophosphatemic rickets

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• autosomal recessive inherited pseudoxanthoma elasticum

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Uncertain_significance. The variant received 5 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr6-131860387-G-A is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 1699960.Status of the report is criteria_provided_single_submitter, 1 stars.
• PP3: Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF. No scorers claiming Uncertain. Scorers claiming Benign: max_spliceai.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_006208.3. 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
	ENPP1	NM_006208.3	MANE Select	c.797G>C	p.Gly266Ala	missense splice_region	Exon 8 of 25	NP_006199.2	P22413

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ENPP1	ENST00000647893.1	MANE Select	c.797G>C	p.Gly266Ala	missense splice_region	Exon 8 of 25	ENSP00000498074.1	P22413
	ENPP1	ENST00000922186.1		c.797G>C	p.Gly266Ala	missense splice_region	Exon 8 of 24	ENSP00000592245.1
	ENPP1	ENST00000513998.5	TSL:5	n.797G>C		splice_region non_coding_transcript_exon	Exon 8 of 25	ENSP00000422424.1	E9PE72

Frequencies

GnomAD3 genomes AF: 0.00000659 AC: 1 AN: 151846 Hom.: 0 Cov.: 32

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

GnomAD4 exome Cov.: 27

GnomAD4 genome AF: 0.00000659 AC: 1 AN: 151846 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74154

African (AFR) AF: 0.00 AC: 0 AN: 41306

American (AMR) AF: 0.00 AC: 0 AN: 15242

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3468

East Asian (EAS) AF: 0.00 AC: 0 AN: 5184

South Asian (SAS) AF: 0.00 AC: 0 AN: 4816

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10522

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.0000147 AC: 1 AN: 67996

Other (OTH) AF: 0.00 AC: 0 AN: 2084

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000378

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.88
BayesDel_addAF	Pathogenic	0.53	D
BayesDel_noAF	Pathogenic	0.52
CADD	Pathogenic	33
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.88	D
Eigen	Pathogenic	0.92
Eigen_PC	Pathogenic	0.81
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	1.0	D
M_CAP	Pathogenic	0.53	D
MetaRNN	Pathogenic	0.99	D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	3.6	H
PhyloP100		9.3
PrimateAI	Pathogenic	0.80	T
PROVEAN	Pathogenic	-5.9	D
REVEL	Pathogenic	0.94
Sift	Pathogenic	0.0	D
Sift4G	Uncertain	0.0060	D
Polyphen		1.0	D
Vest4		0.97
MutPred		0.95		Gain of catalytic residue at G266 (P = 0.0596)
MVP		0.97
MPC		0.82
ClinPred		1.0	D
GERP RS		5.1
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
Varity_R		0.96
gMVP		0.98
Mutation Taster		=38/62	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	0.97
dbscSNV1_RF	Pathogenic	0.77
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: rs121908248; hg19: chr6-132181528;