16-1351967-T-TGGCG

Variant names:

• chr16-1351967-T-TGGCG
• NM_032520.5:c.4_7dupGCGG

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PVS1 PM2 PP5_Moderate

The NM_032520.5(GNPTG):​c.4_7dupGCGG​(p.Ala3GlyfsTer81) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Pathogenic (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: GNPTG NM_032520.5 frameshift
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 0.0570

Genes affected

GNPTG (HGNC:23026): (N-acetylglucosamine-1-phosphate transferase subunit gamma) This gene encodes the gamma sunbunit of the N-acetylglucosamine-1-phosphotransferase complex. This hexameric complex, composed of alpha, beta and gamma subunits, catalyzes the first step in synthesis of a mannose 6-phosphate lysosomal recognition marker. This enzyme complex is necessary for targeting of lysosomal hydrolases to the lysosome. Mutations in the gene encoding the gamma subunit have been associated with mucolipidosis IIIC, also known as mucolipidosis III gamma.[provided by RefSeq, Feb 2010]

TSR3 (HGNC:14175): (TSR3 ribosome maturation factor) Enables transferase activity. Involved in enzyme-directed rRNA pseudouridine synthesis. Predicted to be located in cytosol. [provided by Alliance of Genome Resources, Apr 2022]

ACMG classification

Verdict is Pathogenic. Variant got 12 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant located near the start codon (<100nt), not predicted to undergo nonsense mediated mRNA decay. There are 40 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 16-1351967-T-TGGCG is Pathogenic according to our data. Variant chr16-1351967-T-TGGCG is described in ClinVar as [Pathogenic]. Clinvar id is 2703201.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
GNPTG	NM_032520.5	c.4_7dupGCGG	p.Ala3GlyfsTer81	frameshift_variant	Exon 1 of 11	ENST00000204679.9	NP_115909.1
TSR3	NM_001001410.3	c.-167_-164dupCGCC		upstream_gene_variant		ENST00000007390.3	NP_001001410.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
GNPTG	ENST00000204679.9	c.4_7dupGCGG	p.Ala3GlyfsTer81	frameshift_variant	Exon 1 of 11	1	NM_032520.5	ENSP00000204679.4
TSR3	ENST00000007390.3	c.-167_-164dupCGCC		upstream_gene_variant		1	NM_001001410.3	ENSP00000007390.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Pathogenic:1

Dec 14, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change creates a premature translational stop signal (p.Ala3Glyfs*81) in the GNPTG gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in GNPTG are known to be pathogenic (PMID: 19370764, 20301784). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with GNPTG-related conditions. For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Splicing

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

Publications

No publications associated with this variant yet.

Other links and lift over

hg19: chr16-1401968;