12-101757311-C-T

Position:

• chr12-101757311-C-T

Variant summary

Our verdict is Pathogenic. Variant got 10 ACMG points: 10P and 0B. PVS1_Moderate PM2 PP3_Strong PP5_Moderate

The NM_024312.5(GNPTAB):​c.3336-1G>A variant causes a splice acceptor change. The variant allele was found at a frequency of 0.000000726 in 1,378,002 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: not found (cov: 33)
  • Exomes 𝑓: 7.3e-7 (0 hom.)
• Consequence: GNPTAB NM_024312.5 splice_acceptor
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 5.65

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]

ACMG classification

Verdict is Pathogenic. Variant got 10 ACMG points.

• PVS1: Splicing variant, NOT destroyed by nmd, known LOF gene, truncates exone, which is 0.025987802 fraction of the gene. No cryptic splice site detected. Exon removal is inframe 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 12-101757311-C-T is Pathogenic according to our data. Variant chr12-101757311-C-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 397572.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr12-101757311-C-T is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
GNPTAB	NM_024312.5	c.3336-1G>A		splice_acceptor_variant		ENST00000299314.12
GNPTAB	XM_006719593.4	c.3336-1G>A		splice_acceptor_variant
GNPTAB	XM_011538731.3	c.3255-1G>A		splice_acceptor_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
GNPTAB	ENST00000299314.12	c.3336-1G>A		splice_acceptor_variant		1	NM_024312.5	P1
GNPTAB	ENST00000550718.1	c.148-1G>A		splice_acceptor_variant		3
GNPTAB	ENST00000549738.5	c.87-1G>A		splice_acceptor_variant, NMD_transcript_variant		4
GNPTAB	ENST00000549194.1	n.202-1G>A		splice_acceptor_variant, non_coding_transcript_variant		3

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 7.26e-7 AC: 1 AN: 1378002 Hom.: 0 Cov.: 23 AF XY: 0.00 AC XY: 0 AN XY: 690006

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 9.64e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Pseudo-Hurler polydystrophy;C2673377:Mucolipidosis type II Pathogenic:1

Likely pathogenic, criteria provided, single submitter

research

Diagnostics Division, CENTRE FOR DNA FINGERPRINTING AND DIAGNOSTICS

Jan 01, 2016

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Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.38
CADD	Pathogenic	35
DANN	Uncertain	0.99
Eigen	Pathogenic	1.2
Eigen_PC	Pathogenic	1.0
FATHMM_MKL	Uncertain	0.94	D
MutationTaster	Benign	1.0	D
GERP RS		6.1

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.94
SpliceAI score (max)		1.0		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.59		Position offset: -2
DS_AL_spliceai		1.0		Position offset: -1

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

Publications

LitVar

Other links and lift over

dbSNP: rs397507562; hg19: chr12-102151089;