chr12-101747235-C-T

Variant names:

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2BP4

The NM_024312.5(GNPTAB):c.3700G>A(p.Ala1234Thr) variant causes a missense change. The variant allele was found at a frequency of 0.0000442 in 1,560,096 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.00011 ( 0 hom., cov: 33)

Exomes 𝑓: 0.000038 ( 0 hom. )

Consequence

GNPTAB
NM_024312.5 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:5

Conservation

PhyloP100: 4.37

Variant links:

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 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 1 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (MetaRNN=0.29250067).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
GNPTAB	NM_024312.5 link	c.3700G>A	p.Ala1234Thr	missense_variant	Exon 21 of 21	ENST00000299314.12	NP_077288.2	Q3T906-1
GNPTAB	XM_011538731.3 link	c.3619G>A	p.Ala1207Thr	missense_variant	Exon 21 of 21		XP_011537033.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
GNPTAB	ENST00000299314.12 link	c.3700G>A	p.Ala1234Thr	missense_variant	Exon 21 of 21	1	NM_024312.5	ENSP00000299314.7		Q3T906-1

Frequencies

GnomAD3 genomes

AF:

0.0000986

AC:

AN:

152156

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.000145

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.000327

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.000192

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.00

Gnomad OTH

AF:

0.00143

GnomAD3 exomes

AF:

0.0000359

AC:

AN:

251030

Hom.:

AF XY:

0.0000295

AC XY:

AN XY:

135708

show subpopulations

Gnomad AFR exome

AF:

0.000246

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.000218

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00

Gnomad OTH exome

AF:

0.000164

GnomAD4 exome

AF:

0.0000376

AC:

AN:

1407822

Hom.:

Cov.:

AF XY:

0.0000327

AC XY:

AN XY:

703850

show subpopulations

Gnomad4 AFR exome

AF:

0.000154

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.000102

Gnomad4 SAS exome

AF:

0.0000117

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00000188

Gnomad4 OTH exome

AF:

0.000700

GnomAD4 genome

AF:

0.000105

AC:

AN:

152274

Hom.:

Cov.:

AF XY:

0.0000134

AC XY:

AN XY:

74472

show subpopulations

Gnomad4 AFR

AF:

0.000144

Gnomad4 AMR

AF:

0.000327

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.000192

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00189

Alfa

AF:

0.0000987

Hom.:

Bravo

AF:

0.000117

ExAC

AF:

0.0000577

AC:

Asia WGS

AF:

0.0130

AC:

AN:

3478

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:5

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Pseudo-Hurler polydystrophy;C2673377:Mucolipidosis type II

Uncertain:2

Oct 31, 2018

Fulgent Genetics, Fulgent Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Apr 29, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces alanine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 1234 of the GNPTAB protein (p.Ala1234Thr). The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. This variant has not been reported in the literature in individuals affected with GNPTAB-related conditions. ClinVar contains an entry for this variant (Variation ID: 574283). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt GNPTAB protein function with a negative predictive value of 80%. 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. -

Inborn genetic diseases

Uncertain:1

Aug 17, 2022

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.3700G>A (p.A1234T) alteration is located in exon 21 (coding exon 21) of the GNPTAB gene. This alteration results from a G to A substitution at nucleotide position 3700, causing the alanine (A) at amino acid position 1234 to be replaced by a threonine (T). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

not provided

Uncertain:1

Jul 27, 2021

Mayo Clinic Laboratories, Mayo Clinic

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Mucolipidosis type II

Uncertain:1

Jan 24, 2020

Natera, Inc.

Significance: Uncertain significance

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.099

BayesDel_addAF

Benign

-0.066

BayesDel_noAF

Uncertain

-0.040

CADD

Benign

DANN

Uncertain

1.0

DEOGEN2

Benign

0.13

Eigen

Uncertain

0.47

Eigen_PC

Uncertain

0.56

FATHMM_MKL

Uncertain

0.96

LIST_S2

Uncertain

0.92

M_CAP

Benign

0.045

MetaRNN

Benign

0.29

MetaSVM

Uncertain

0.77

MutationAssessor

Benign

1.7

PrimateAI

Uncertain

0.55

PROVEAN

Benign

-1.1

REVEL

Uncertain

0.44

Sift

Benign

0.089

Sift4G

Benign

0.57

Polyphen

0.97

Vest4

0.45

MVP

0.95

MPC

0.68

ClinPred

0.076

GERP RS

5.9

Varity_R

0.091

gMVP

0.55

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

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