chr12-101768036-C-A

Variant names:

• chr12-101768036-C-A
• rs1060499680
• ENST00000549940.5:c.1409G>T

Variant summary

Our verdict is Pathogenic. The variant received 14 ACMG points: 14P and 0B. PM2 PP3_Strong PP5_Very_Strong

The ENST00000549940.5(GNPTAB):​c.1409G>T​(p.Gly470Val) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,738 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: GNPTAB ENST00000549940.5 missense
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:3
• Conservation: PhyloP100: 7.29
• Publications: 0 publications found

Genes affected

GNPTAB (HGNC:29670): (N-acetylglucosamine-1-phosphate transferase subunits alpha and beta) This gene encodes two of three subunit types of the membrane-bound enzyme N-acetylglucosamine-1-phosphotransferase, a heterohexameric complex composed of two alpha, two beta, and two gamma subunits. The encoded protein is proteolytically cleaved at the Lys928-Asp929 bond to yield mature alpha and beta polypeptides while the gamma subunits are the product of a distinct gene (GeneID 84572). In the Golgi apparatus, the heterohexameric complex catalyzes the first step in the synthesis of mannose 6-phosphate recognition markers on certain oligosaccharides of newly synthesized lysosomal enzymes. These recognition markers are essential for appropriate trafficking of lysosomal enzymes. Mutations in this gene have been associated with both mucolipidosis II and mucolipidosis IIIA.[provided by RefSeq, May 2010]

GNPTAB Gene-Disease associations (from GenCC):

• GNPTAB-mucolipidosis

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
• mucolipidosis

  Inheritance: AR Classification: DEFINITIVE Submitted by: Myriad Women’s Health
• mucolipidosis type II

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, Labcorp Genetics (formerly Invitae), Ambry Genetics, PanelApp Australia, Genomics England PanelApp
• mucolipidosis type III, alpha/beta

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, Ambry Genetics, G2P, Genomics England PanelApp

ACMG classification

Our verdict: Pathogenic. The variant received 14 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF, max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.
• PP5: Variant 12-101768036-C-A is Pathogenic according to our data. Variant chr12-101768036-C-A is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 397559.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: ENST00000549940.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	GNPTAB	NM_024312.5	MANE Select	c.1408+1G>T		splice_donor intron	N/A	NP_077288.2

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	GNPTAB	ENST00000549940.5	TSL:1	c.1409G>T	p.Gly470Val	missense	Exon 11 of 11	ENSP00000449150.1
	GNPTAB	ENST00000299314.12	TSL:1 MANE Select	c.1408+1G>T		splice_donor intron	N/A	ENSP00000299314.7
	GNPTAB	ENST00000552009.1	TSL:3	n.67+1G>T		splice_donor intron	N/A

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461738 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 727192

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26134

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.0000116 AC: 1 AN: 86252

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53420

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111878

Other (OTH) AF: 0.00 AC: 0 AN: 60382

GnomAD4 genome Cov.: 33

ClinVar

ClinVar submissions as Germline

Significance: Pathogenic/Likely pathogenic

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
2	-	-	Pseudo-Hurler polydystrophy;C2673377:Mucolipidosis type II (2)
1	-	-	Mucolipidosis type II (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.29
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.51
CADD	Pathogenic	33
DANN	Uncertain	0.99
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	0.89
FATHMM_MKL	Pathogenic	0.98	D
M_CAP	Pathogenic	0.32	D
PhyloP100		7.3
ClinPred		0.98	D
GERP RS		5.7
Mutation Taster		=8/92	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.91
SpliceAI score (max)		0.99		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.99		Position offset: 1

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

Other links and lift over

dbSNP: rs1060499680; hg19: chr12-102161814;