rs376679416

chr16-1361798-G-Achr16-1361798-G-Cchr16-1361798-G-T

Variant summary

Our verdict is Pathogenic. Variant got 20 ACMG points: 20P and 0B. PVS1PM2PP3_ModeratePP5_Very_Strong

The NM_032520.5(GNPTG):c.233+1G>A variant causes a splice donor change. The variant allele was found at a frequency of 0.0000105 in 1,613,800 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★★).

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 33)

Exomes 𝑓: 0.000010 ( 0 hom. )

Consequence

GNPTG
NM_032520.5 splice_donor

Scores

Splicing: ADA: 0.9999

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:6

Conservation

PhyloP100: 6.91

Variant links:

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]

GNPTG links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 20 ACMG points.

PVS1

Splicing variant, LoF is a know mechanism of disease, Cryptic splice site detected, with MaxEntScore 5.4, offset of 11, new splice context is: aggGTgggt. Cryptic site results in frameshift change. If cryptic site found is not functional and variant results in exon loss, it results in frameshift change.

PM2

Very rare variant in population databases, with high coverage;

PP3

Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF, max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.

PP5

Variant 16-1361798-G-A is Pathogenic according to our data. Variant chr16-1361798-G-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 552294.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr16-1361798-G-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
GNPTG	NM_032520.5 linkuse as main transcript	c.233+1G>A		splice_donor_variant		ENST00000204679.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
GNPTG	ENST00000204679.9 linkuse as main transcript	c.233+1G>A		splice_donor_variant		1	NM_032520.5	P1

Frequencies

GnomAD3 genomes

AF:

0.0000131

AC:

AN:

152128

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000483

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

GnomAD3 exomes

AF:

0.0000119

AC:

AN:

251286

Hom.:

AF XY:

0.00000736

AC XY:

AN XY:

135848

show subpopulations

Gnomad AFR exome

AF:

0.000123

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.0000463

Gnomad NFE exome

AF:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000103

AC:

AN:

1461672

Hom.:

Cov.:

AF XY:

0.00000825

AC XY:

AN XY:

727140

show subpopulations

Gnomad4 AFR exome

AF:

0.0000299

Gnomad4 AMR exome

AF:

0.0000224

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000252

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.0000188

Gnomad4 NFE exome

AF:

0.00000899

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000131

AC:

AN:

152128

Hom.:

Cov.:

AF XY:

0.0000269

AC XY:

AN XY:

74318

show subpopulations

Gnomad4 AFR

AF:

0.0000483

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

Alfa

AF:

0.0000489

Hom.:

Bravo

AF:

0.0000189

ESP6500AA

AF:

0.000227

AC:

ESP6500EA

AF:

0.00

AC:

ExAC

AF:

0.0000247

AC:

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:6

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

GNPTG-mucolipidosis

Pathogenic:4

Likely pathogenic, criteria provided, single submitter	clinical testing	Medical Molecular Genetics Department, Human Genetics and Genome Research Division, National Research Centre	Dec 10, 2018	- -
Pathogenic, criteria provided, single submitter	clinical testing	Genome-Nilou Lab	Nov 07, 2021	- -
Likely pathogenic, criteria provided, single submitter	clinical testing	Myriad Genetics, Inc.	Nov 19, 2021	NM_032520.4(GNPTG):c.233+1G>A is a canonical splice variant classified as likely pathogenic in the context of mucolipidosis III gamma. c.233+1G>A has been observed in cases with relevant disease (PMID: 30507725). Functional assessments of this variant are not available in the literature. c.233+1G>A has been observed in population frequency databases (gnomAD: AFR 0.01%). In summary, NM_032520.4(GNPTG):c.233+1G>A is a canonical splice variant in a gene where loss of function is a known mechanism of disease and is predicted to disrupt protein function. Please note: this variant was assessed in the context of healthy population screening. -
Pathogenic, no assertion criteria provided	clinical testing	Natera, Inc.	Sep 10, 2020	- -

not provided

Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Mar 08, 2023	Not observed at significant frequency in large population cohorts (gnomAD); Canonical splice site variant predicted to result in a null allele in a gene for which loss of function is a known mechanism of disease; This variant is associated with the following publications: (PMID: 30882951, 30507725, Eissa[article]2022) -
Pathogenic, criteria provided, single submitter	clinical testing	Invitae	Jan 04, 2024	This sequence change affects a donor splice site in intron 4 of the GNPTG gene. It is expected to disrupt RNA splicing. Variants that disrupt the donor or acceptor splice site typically lead to a loss of protein function (PMID: 16199547), and loss-of-function variants in GNPTG are known to be pathogenic (PMID: 19370764, 20301784). This variant is present in population databases (rs376679416, gnomAD 0.01%). Disruption of this splice site has been observed in individual(s) with clinical features of mucolipidosis III gamma (PMID: 30507725, 30882951). It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 552294). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_addAF

Pathogenic

0.46

BayesDel_noAF

Uncertain

0.11

Cadd

Pathogenic

Dann

Uncertain

0.99

Eigen

Pathogenic

1.0

Eigen_PC

Pathogenic

0.84

FATHMM_MKL

Pathogenic

0.97

MutationTaster

Benign

1.0

GERP RS

4.5

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Splicing

Name

Calibrated prediction

Score

Prediction

dbscSNV1_ADA

Pathogenic

1.0

dbscSNV1_RF

Pathogenic

0.95

SpliceAI score (max)

0.67

Details are displayed if max score is > 0.2

DS_DL_spliceai

0.67

Position offset: -1

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

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over