16-1351967-TGGC-T

Variant names:

• chr16-1351967-TGGC-T
• rs1344845304
• NM_032520.5:c.8_10delCGG

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_032520.5(GNPTG):​c.8_10delCGG​(p.Ala3del) variant causes a disruptive inframe deletion change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000132 in 151,578 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency: Genomes: 𝑓 0.000013 (0 hom., cov: 32)
• Consequence: GNPTG NM_032520.5 disruptive_inframe_deletion
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 0.840

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 Uncertain_significance. Variant got 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
GNPTG	NM_032520.5	c.8_10delCGG	p.Ala3del	disruptive_inframe_deletion	Exon 1 of 11	ENST00000204679.9	NP_115909.1
TSR3	NM_001001410.3	c.-166_-164delGCC		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.8_10delCGG	p.Ala3del	disruptive_inframe_deletion	Exon 1 of 11	1	NM_032520.5	ENSP00000204679.4
TSR3	ENST00000007390.3	c.-166_-164delGCC		upstream_gene_variant		1	NM_001001410.3	ENSP00000007390.2

Frequencies

GnomAD3 genomes AF: 0.0000132 AC: 2 AN: 151578 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000484

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: 0.00

Gnomad OTH AF: 0.00

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome AF: 0.0000132 AC: 2 AN: 151578 Hom.: 0 Cov.: 32 AF XY: 0.0000135 AC XY: 1 AN XY: 74022

Gnomad4 AFR AF: 0.0000484

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

GNPTG-mucolipidosis Uncertain:1

Nov 17, 2017

Counsyl

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

not provided Uncertain:1

Aug 24, 2021

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant, c.8_10del, results in the deletion of 1 amino acid(s) of the GNPTG protein (p.Ala3del), but otherwise preserves the integrity of the reading frame. The frequency data for this variant in the population databases is considered unreliable, as metrics indicate insufficient coverage at this position in the ExAC database. This variant has not been reported in the literature in individuals affected with GNPTG-related conditions. ClinVar contains an entry for this variant (Variation ID: 555097). Experimental studies and prediction algorithms are not available or were not evaluated, and the functional significance of this variant is currently unknown. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

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: rs1344845304; hg19: chr16-1401968;